Single-cell RNA sequencing (scRNA-seq) has generated a rapidly expanding collection of public datasets that provide insight into development, disease, and therapy. However, researchers lack an end-to-end solution for seamlessly retrieving, preprocessing, integrating, and analyzing these data because existing tools address only isolated steps and require manual curation of accessions, metadata, and technical variability, known as batch effects. In this study, we developed Celline, a Python package that executes an entire workflow using a single-line commands per step. Celline automatically gathers raw single-cell RNA-seq data from multiple public repositories and extracts metadata using large language models. It then wraps established tools, including Scrublet for doublet removal, Seurat and Scanpy for quality control and cell-type annotation, Harmony and scVI for batch correction, and Slingshot for trajectory inference, into one-line commands, enabling seamless integrative analyses. To validate Celline-acquired data quality and the integrated framework's practical utility, we applied it to 2 mouse brain cortex datasets from embryonic days 14.5 and 18. Technical validation demonstrated that Celline successfully retrieved data, standardized metadata, and enabled standard analyses that removed low-quality cells, annotated 11 major cell types, improved integration quality (scIB score +0.22), and completed trajectory analysis. Thus, Celline transforms scattered public scRNA-seq resources into unified, analysis-ready datasets with minimal effort. Its modular design allows pipeline extension, encourages community-driven advances, and accelerates the discovery of single-cell data.

We reformulate the Leslie effects that describe the dynamic cross-couplings in chiral liquid crystals driven by the transport of heat, electric charge, and mass. The Ericksen-Leslie model is extended in the linear response framework by representing nematic order with the Q tensor. Subsequently, the thermodynamic uncertainty relation is applied to identify the upper bounds of the Leslie cross-coupling coefficients. We reveal that the cross-coupling coefficients are dependent on the scalar order parameter and vanish in the isotropic phase. In addition, the chirality of the phase allows torque induced by a transport current parallel to the director. The mutual signs of the Leslie thermohydrodynamic and thermomechanical coefficients are likely to be opposite in calamitic liquid crystals, as suggested by recent experimental observations. Our model is applicable to the thermal, chemical, and electrical Leslie effects. The present arguments suggest that a common underlying principle may govern both the Leslie effects and the thermal Edelstein effect in chiral solid crystals attributed to chiral phonons.

An ML-based workflow doubles crystal structure prediction success by narrowing the search space for organic molecules.

Designing 2D mesoporous metal-organic framework (MOF) nanosheets to overcome the limitations of bulk MOF counterparts, with a focus on enabling smooth mass transport, presents an attractive yet challenging endeavor. Here, a novel bottom-up interface-directed co-assembly method is presented for the synthesis of ultrathin 2D mesoporous UiO-66(Ce) nanosheets. The method utilizes an interface-directed co-assembly of amphiphilic perfluorooctanoic acid-induced lipid bilayers and spherical micelles from PS-b-PEO block copolymers to form unique 2D sandwich-like assemblies that guide the creation of 2D mesoporous UiO-66(Ce). The resultant 2D mesoporous UiO-66(Ce), with ≈23 nm pore diameters and a thickness that can be tuned from 3 to 150 nm, represents a substantial advancement in the application of MOFs for environmental remediation. As a model reaction, the U(VI) photoreduction benefits from the through-mesopores of its 2D morphology, which are absent in previously reported UiO-66(Ce), as they shorten the diffusion path, thereby improving mass transport and accessibility to active sites. This report demonstrates the significant role of existing mesopores in MOFs and the shape control of MOFs.

Mechanical stretch critically influences skeletal muscle physiology, yet its role in myoblast differentiation and the associated molecular mechanisms have not been fully clarified. This study investigated the effects of uniaxial cyclic mechanical stretch (UnCyMSt) on differentiation of mouse myoblast C2C12 cells, focusing particularly on the potential involvement of eukaryotic initiation factor 2 alpha (eIF2α), a key regulator maintaining muscle stem cell quiescence. To apply mechanical stretch, C2C12 cells were cultured on polydimethylsiloxane surfaces covalently immobilized with collagen (Col-GA-PDMS), ensuring stable cell adhesion under UnCyMSt, whereas cells cultured on physically adsorbed collagen surfaces (Col-PDMS) detached under similar conditions. Under differentiation conditions, UnCyMSt markedly inhibited myoblast differentiation, as evidenced by suppressed expression of the differentiation marker myogenin. Additionally, stretched cells aligned perpendicular to the direction of mechanical stretch application. Given the established role of phosphorylated eIF2α (p-eIF2α) in maintaining myoblast quiescence, we investigated whether UnCyMSt inhibits differentiation by modulating eIF2α phosphorylation at serine 51. UnCyMSt did not prevent the progressive dephosphorylation of eIF2α during differentiation induction. Correspondingly, expression levels of activating transcription factor 4 (ATF4), downstream of p-eIF2α, also decreased under UnCyMSt. Our results demonstrate that UnCyMSt inhibits C2C12 myoblast differentiation without sustained phosphorylated eIF2α, suggesting the involvement of alternative mechanosensitive signaling pathways. These findings provide new insights into mechanical regulation of muscle differentiation and highlight the need for further exploration into stretch-responsive molecular mechanisms influencing myogenesis.

Photomechanical organic crystals have gained considerable attention both from the perspective of fundamental research and applications in actuators and soft robots. Needle‐like crystals of 1,4‐di‐p‐toluidinoanthraquinone (1), an aminoanthraquinone derivative, oscillate when irradiated with unpolarized pulsed light, based on photothermally resonated natural vibration. However, their photomechanical motion in response to polarized light has not yet been investigated in detail. In this study, the photomechanical behavior of 1 upon linearly polarized light irradiation is examined. The crystal oscillats with a different magnitude depending on the polarization direction of the incident light. The greater the absorption, the larger and more significant the oscillation. Furthermore, the crystal exhibits different oscillation anisotropy depending on the wavelength of the light (375, 520, and 638 nm). This is because the crystal exhibits distinct absorption anisotropy depending on the wavelength of the light, which originates from the directions of the transition dipole moments. This work highlights that the polarization direction can serve as a control parameter, providing an additional degree of freedom to photomechanical crystals.

Cannabinoid receptor type 1 (CB1R) is the key modulator of neuronal viability. CB1R antagonists provide neuroprotective effects on neurotoxicity caused by e.g. neuronal injury. However, the underlying mechanisms and potential limitations of CB1R antagonism remain unclear. Here we investigated the impact of environmental conditions on CB1R antagonist effects. We have found that cell-permeable CB1R antagonists, rimonabant and AM251, induced cell death in human neuroblastoma SH-SY5Y cells under serum-free conditions. Mitochondrial morphological analysis revealed mitochondrial swelling characterized by their network fragmentation and cristae reduction. Phosphoproteomics analysis showed the ER stress signaling pathway PERK/eIF2α/ATF4/CHOP, leading to caspase-dependent apoptosis. These results suggest that CB1R antagonists promote apoptosis via mitochondrial damage and ER stress under serum-free conditions in SH-SY5Y cells. Our findings indicate that while CB1R antagonists may be neuroprotective in certain conditions, they may also pose a neurotoxic risk in environments characterized by cellular stress or nutrient deprivation.

Cannabinoid receptor type 1 (CB1R) plays a key role in neuronal homeostasis, synaptic plasticity, and neuroprotection. CB1R antagonists typically protect against CB1R agonists-induced neurotoxicity. However, we previously found that the CB1R antagonists rimonabant and its analog AM251 can also be neurotoxic: under serum-free conditions, these compounds induce apoptosis in human neuroblastoma SH-SY5Y cells through mitochondrial damage and endoplasmic reticulum (ER) stress. To elucidate the mechanisms of this neurotoxicity, we examined the effects of CB1R agonists. We co-treated SH-SY5Y cells with rimonabant or AM251 in combination with either the CB1R agonist arachidonyl 2-chloroethylamide (ACEA) or WIN 55212-2 mesylate (WIN). ACEA, but not WIN, protected cells from rimonabant- and AM251-induced apoptosis. While ACEA had only a limited effect on mitochondrial damage, it significantly reduced phosphorylation of the eukaryotic initiation factor 2 alpha (eIF2α), a key marker of ER stress. Given that ACEA also functions as an agonist of transient receptor potential vanilloid 1 (TRPV1), we investigated its role in ACEA-mediated neuroprotection. The TRPV1 antagonist capsazepine blocked ACEA's protective effects, suggesting that ACEA acts through TRPV1 rather than CB1R. ACEA also prevented apoptosis induced by camptothecin, a well-established apoptosis inducer, through a similar capsazepine-sensitive mechanism, demonstrating its broader protective effects against apoptosis. These findings indicate that rimonabant and AM251 induce neurotoxicity independently of CB1R under serum-free conditions and that ER stress is likely to be a key target of CB1R-independent neuroprotection by ACEA. Our study highlights the complexity of CB1R ligand-associated neurotoxicity and neuroprotection.

Gryllus assimilis, commonly known as Jamaican field cricket, is an edible insect with significant economic value in sustainable food production. Despite its importance, a high-quality reference genome of G. assimilis has not yet been published. Here, we report a chromosome-level reference genome of G. assimilis based on Oxford Nanopore Technologies (ONT) sequencing, Illumina sequencing, and Hi-C technologies. The assembled genome has a total length of 1.60 Gbp with a scaffold N50 of 102 Mbp, and 96.80% of the nucleotides was assigned to 15 chromosome-scale scaffolds. The assembly completeness was validated using BUSCO, achieving 99.5% completeness against the arthropoda database. We predicted 27,645 protein-coding genes, and 825 Mb repetitive elements were annotated in the reference genome. This reference genome of G. assimilis can provide a basis for the subsequent development of genomic resources, offering insights for future functional genomic studies, comparative genomics, and DNA-informed breeding of this species.

Trimetallic systems have garnered considerable attention in (electro)catalysis due to the synergistic effects resulting from the combination of three different metals. However, achieving precise control over the positioning of various metals and understanding the relationship between structure and performance remains challenging. This study introduces an approach for synthesizing Pd@Pt@Au mesoporous nanoparticles (MNPs) with distinct core-shell Pd@Pt structures, featuring well-dispersed isolated Au islands on the outer shell, improving the plasmonic effect. The electrocatalytic performance of Pd@Pt@Au MNPs in the methanol oxidation reaction (MOR) is assessed under light-induced and light-independent conditions. The results indicate significantly enhanced activity compared to commercial Pt black, with catalytic activity during MOR increasing approximately 7.5-fold under light irradiation. The external placement of Au on the shell of Pd@Pt@Au MNPs provides superior plasmonic enhancement, thereby contributing to improved catalytic performance under light irradiation. This investigation sheds light on the controlled synthesis of trimetallic MNPs and their catalytic applications, underscoring the importance of precise Au positioning for optimizing performance.

Electrochemical adsorption offers a promising approach for the separation of monovalent cations, which is an important but challenging subject in separation science. However, progress in this area has been hampered by the lack of suitable materials with effective ion selectivity. In this work, we present the synthesis of covalent organic frameworks (COFs) functionalized with a series of crown ethers (NCx-TAB-COFs, x donate 12, 15, 18, indicating the size of crown ether) for the efficient and highly selective electrochemical capture of monovalent cations. In our design, crown ether moieties act as confinement sites, imparting high selectivity for different monovalent cations depending on the cavity dimensions of the crown ether present. COFs electrodes prepared using the novel crown-COFs exhibit superior performance for the selective sequestration of monovalent (alkali metal) cations. Notably, 18-crown-6 ether-substituted COF (NC18-TAB-COF) shows a remarkable selectivity (14.26) for K+ over Na+ and a substantial Rb+/Na+ selectivity of 22.4. Furthermore, NCx-TAB-COFs maintain their remarkable selectivity and capacity under mixed-cation conditions. Density functional theory calculations and molecular dynamics simulations suggest that the unexpectedly high selectivity for larger cations is likely due to diverse binding modes in conjunction with the porous structure of the COFs. Given their lower dehydration-free energies and smaller hydrodynamic radii, K+, Rb+, and Cs+ more readily permeate the confined channels of COFs. In contrast, Na+ and Li+, with higher dehydration-free energies and hydrodynamic radii, diffuse into the NCx-TAB-COFs structure at a much slower rate and are bound predominantly to the surfaces of the COFs.

Titania films with a completely controlled hierarchical structure, at microscopic, mesoscopic, and macroscopic scales, are successfully prepared by carefully combining "top-down" and "bottom-up" nanoprocesses. The titania films are composed of regularly arranged anatase nanocrystals, which form a 2D hexagonal mesostructure with cylindrical mesopores. Furthermore, the cylindrical mesopores are aligned in one direction in the plane of the film over the whole area. Thus, hierarchical structural regularities over multiple length scales, i.e., atomic (10-10 m), mesoscopic (10-8 m), and macroscopic (10-2 m) scales, are achieved. The mesoporous titania films with a controlled alignment are prepared via sol-gel chemistry using the self-assembly process of amphiphilic molecules combined with a lithographically prepared anisotropic substrate with a fine wavy cross-section. The carefully designed sol-gel process using Pluronic P123 as a structure-directing agent allows the retention of the aligned mesoporous structure as well as the formation of crack-free films even after the crystallization of titania. The anisotropic mesoporous structure with pore walls composed of high-refractive-index crystalline titania exhibits remarkable optical anisotropy, birefringence. This full-multiscale structural control of an inorganic material, from atomic to centimeter scales, affords distinguished functionalities to artificially prepared nanomaterials, paving the way for creating new values.

For the single crystals of thalidomide (C13H10N2O4, TD) grown by the solvent evaporation method, the temperature dependences of the crystal structures have been investigated over a wide temperature range between 100 and 423.15 K. Comparing the α-form of a racemic TD crystal, which consists of symmetric heterochiral dimers and belongs to P21/n space group, with the enantiomeric TD crystal, which belongs to P21 and consists of asymmetric (pseudosymmetric) homochiral dimers, there have been clear differences in the temperature-dependent changes of the lattice parameters, the isobaric linear thermal expansion coefficients (along the crystallographic and the principal Cartesian axes), the volumetric expansion coefficients of the unit cell, and the structures of hydrogen-bonded dimer in the crystal such as intra- and intermolecular dihedral angles, cavities (reaction cavities), and the hydrogen-bond length. In the asymmetric homochiral dimers, one monomer with a larger reaction cavity changes its intramolecular dihedral angle with temperature, while the other monomer with a smaller cavity does not. In contrast, in the symmetric heterochiral dimers, two monomers with the same cavity volume similarly change their intramolecular dihedral angles with the temperature. Such differences in the temperature-dependent conformational changes between asymmetric and symmetric dimers cause differences between enantiomeric and racemic crystals.

Abstract

Photomechanical crystals are fascinating candidates for their applications to light-fueled actuators. Over the past two decades diverse examples have been reported. However, research that revealed the structure–photomechanical behavior relationships is rare. Here, we focused on three polymorphs of a salicylideneaniline derivative with a 3-carboxy group in the enol form, 1α, 1β, and 1γ. All polymorphic crystals were stable in air at room temperature and underwent reversible photoisomerization in the solid state. Absorption spectrum measurements revealed that the γ form, previously considered as non-photochromic, is weakly photochromic. Upon ultraviolet (UV) light irradiation, thin 1α and 1β crystals bent away from the light source quickly and slowly, respectively, through photoisomerization while a thin 1γ crystal bent toward the illumination direction by the same mechanism. The 1α and 1β crystals exhibited high repeatability for photomechanical bending, maintaining their original shape over 100 cycles. In contrast, the 1γ crystal gradually deformed during repeated bending because of its plasticity due to the slip planes. Besides the 1α crystal underwent an irreversible thermal phase transition to the 1β and 1γ crystals upon heating. This work is expected to highlight the relationship between structures and actuation performance, especially bending repeatability, of photomechanical crystals.

We employed two types of machine learning for molecular design and experimental optimization to efficiently maximize the blocking force.

In this report, ghostly ultra-trace amounts of alanine in alanine-doped triglycine sulfate crystal were directly observed by solid-state nuclear magnetic resonance, and the presence of two chemical states in the cation form and neutral form in the doped alanine was revealed. As the result, the crystal structure of alanine-doped triglycine sulfate was determined for the first time.

Abstract

Photomechanical crystals exhibit mechanical motion upon light irradiation and may thus find applications as actuators. Over the last decades, many photomechanical organic crystals have been developed, commonly via photochemical reactions, particularly photoisomerization. However, photochemical crystal actuation is associated with several drawbacks, including a limited number of available crystals, slow actuation speed (<5 Hz), and narrow wavelength range (<550 nm). Such constraints have hindered the widespread use of crystals as actuation materials. In this minireview, we focus on crystal actuation by employing more universal physical phenomena (the photothermal effect and photothermally resonated natural vibration) and quantitatively evaluate actuation performance. Both mechanisms, particularly the latter, outperformed conventional photomechanical crystal activation in terms of both speed (maximum: 1,350 Hz) and the useful wavelength range (ultraviolet to near‐infrared). The oscillation frequencies of the crystals exceeded those of polymers, efficiently filling the gap between soft and hard materials. Both the photothermal effect and natural vibration can actuate any crystal that absorbs light. These two versatile physical actuation mechanisms could expand 40 years of research on photomechanical crystals—which had been based on photochemical reactions—from the realm of chemistry into engineering and lead to their practical applications in actuators and soft robots.

Copper oxide high-temperature superconductors, such as Bi2Sr2CaCu2O8+δ (Bi2212), have garnered extensive research interest due to their high critical temperatures (Tc) surpassing the Bardeen-Cooper-Schrieffer (BCS) limit. The two-dimensional CuO₂ plane is widely regarded as the most crucial element of high-Tc cuprate superconductors. The anisotropy of this CuO₂ layer remains a topic of ongoing interest. Although a few experimental results have reported strong optical anisotropy in both ab and ac-planes of Bi2212 through optical "reflectivity" measurements, there is a lack of studies focusing on the optical anisotropy of these materials using optical "transmittance" measurements by utilizing ultraviolet and visible light. Using a generalized high-accuracy universal polarimeter, we observed significant linear birefringence and linear dichroism peaks in the UV region at room temperature. To investigate the origin of the significant optical anisotropy, single crystals of Bi2-xPbxSr2CaCu2O8+δ with different lead contents (x = 0, 0.4, and 0.6) were grown using the floating zone method, and the wavelength dependencies of linear birefringence and linear dichroism along the c axis were measured. The insights gained into the optical anisotropy of Bi2-xPbxSr2CaCu2O8+δ from this study are significant for discussing its origin of the mechanism of high-Tc superconductivity.

Abstract

Covalent organic frameworks (COFs) are promising high‐performance capacitive deionization (CDI) materials. Strategies to optimize CDI performance of COFs focus largely on hybridization with conductive substrates, to improve their their intrinsically poor conductivity. A new structure‐function relationship between COFs and their substrates is proposed here based on substrate‐induced surface curvature. Graphene (zero‐curvature) and carbon nanotubes (CNT, curved) are selected as COF growthsubstrates to assess the effect of curvature engineering effect on CDI performance of TpPa‐SO ₃ H‐COF. Ultrahigh ion (Na ⁺ ) adsorption capacity (58.74 mg g ⁻¹ ) is achieved by CNT‐COF hybrid ( cf . compared to graphene‐COF hybrid 34.20 mg g ⁻¹ ), demonstrating the significance of curvature engineering. Notably, the corresponding salt (NaCl) adsorption capacity of CNT‐COF hybrid reaches 149.25 mg g ⁻¹ in 1000 ppm at 1.2 V, representing state‐of‐the‐art CDI performance, and the highest value among organic CDI electrodes. X‐ray photoelectron spectroscopy and theoretical calculations subsequently reveal that substrate curvature can induce local strain, which regulates charge distribution within the COF skeleton, causing a lower binding energy state for Na ⁺ adsorption. Electrochemical quartz crystal microbalance measurements revealed faster Na ⁺ adsorption kinetics of CNT‐COF due to regulated charge distribution within COF skeleton induced by substrate curvature. This work gives new insight into design of COF materials based on curvature engineering.

Abstract

Capacitive deionization is an efficient and cost-effective technology for ion removal from brackish water. Here, we demonstrate a sulfonate-functionalized covalent organic framework as a novel faradaic cathode material for capacitive deionization applications. Due to its orderly arranged adsorption units in the covalent organic framework, the resulting covalent organic framework demonstrates a superior sodium cations removal capacity of 19.56 mg g−1 and a maximum desalination rate of 3.15 mg g−1 s−1 in a 500 ppm NaCl solution at 1.2 V.

Abstract

The rational design of efficient catalysts for uric acid (UA) electrooxidation, as well as the establishment of structure‐activity relationships, remains a critical bottleneck in the field of electrochemical sensing. To address these challenges, herein, a hybrid catalyst that integrates carbon‐supported Pt nanoparticles and nitrogen‐coordinated Mn single atoms (Pt_NPs/MnNC) is developed. The metal‐metal interaction during annealing affords the construction of metallic‐bonded Pt−Mn pairs between Pt_NPs and Mn single atoms, facilitating the electron transfer from Pt_NPs to the support and thereby optimizing the electronic structure of catalysts. More importantly, experiments and theoretical calculations provide visual proof for the ‘incipient hydrous oxide adatom mediator’ mechanism for UA oxidation. The Pt−Mn pairs first adsorb OH* to construct the bridged Pt−OH−Mn mediators to serve as a highly active intermediate for N−H bond dissociation and proton transfer. Benefiting from the unique electronic and geometric structure of the catalytic center and reactive intermediates, Pt_NPs/MnNC exhibits superior electrooxidation performance. The electrochemical sensor based on Pt_NPs/MnNC enables sensitive detection and discrimination of UA and dopamine in serum samples. This work offers new insights into the construction of novel electrocatalysts for sensitive sensing platforms.

Abstract

Photo‐triggered phase transition is a new type of phase transition in which a photochromic crystal with a thermal phase transition transforms into an identical high‐temperature phase in a temperature region lower than the thermal phase transition temperature upon light irradiation. Here, we report a second crystal that exhibits a photo‐triggered phase transition, thereby demonstrating that the photo‐triggered phase transition is a general phenomenon that occurs in crystals. When the chiral salicylidenephenylethylamine crystal was irradiated with ultraviolet (UV) light, the photo‐triggered phase transition occurred in the temperature range −30 to −10 °C. The photo‐triggered phase transition is induced by local stress due to trans‐keto molecules produced by photoisomerization near the irradiated surface. Crystal cantilevers exhibited stepwise bending by the combination of the photo‐triggered phase transition and photoisomerization. Alternate irradiation with UV and visible light achieved locomotion of single crystals driven by repeated stepwise bending. Finally, a detailed comparison of photo‐triggered and non‐photo‐triggered phase transition crystals revealed that a sufficient molecular conformation change in affordable crystal voids, smooth photoisomerization, and most likely a chiral molecular arrangement are required for inducing the photo‐triggered phase transition.

Atomically dispersed Pt-group metals are promising as nanocatalysts because of their unique geometric structures and ultrahigh atomic utilization. However, loading isolated Pt-group metals in single-atom alloys (SAAs) with distinctive bimetallic sites is challenging. In this study, we present amorphous mesoporous Ni boride (Ni-B) as an ideal substrate to uniformly disperse Pt atoms with tunable loadings (1.7 to 12.2 wt %). The effect of the morphology, composition, and crystal phase of the Ni-B host on the growth and dispersion of Pt atoms is discussed. The resulting amorphous Pt-Ni-B mesoporous nanospheres exhibit superior electrocatalytic H ₂ evolution performance in acidic media. This strategy holds the potential to synthesize a diverse library of mesoporous amorphous Pt-group SAAs, by leveraging functional amorphous nanostructured 3 d transition-metal borides as substrates, thereby proposing a comprehensive strategy to control atomically dispersed Pt-group metals.

Nanoporous Ba _0.85 Ca _0.15 (Ti _0.9 Zr _0.1 )O ₃ (BCZT) films, as lead-free piezoelectrics, exhibited a d ₃₃ ∼10 times higher than nonporous BCZT, making them promising for high-density dielectric capacitors and energy harvesters.

Abstract<p>Photomechanical crystals have applications in light-fuelled actuators and soft robots. Herein, we describe light-responsive, versatile, anthraquinone dye crystal oscillators actuated via natural vibrations that are resonated by a photothermal effect. A black needle-shaped crystal cantilever oscillates at 70 Hz in the first mode of natural vibration upon irradiation by broad-wavelength light ranging from the ultraviolet through the visible to the near infrared, and also under continuous-wavelength light (400–2000 nm). The second and third natural vibration modes are induced at higher frequencies (530 and 1350 Hz) and evidence complex flagellum-like motions. The frequency can be readily tuned by moving the support of a crystal piece; this is analogous to playing a guitar. The crystal exhibits high durability (more than 10,000 cycles): the high elasticity prevents deterioration. Oscillatory motions can be designed via simulations using finite element analysis. This work will facilitate the use of photomechanical crystals in light-fuelled soft robots.</p>

ABSTRACT

Circadian rhythms are indispensable intrinsic programs that regulate the daily rhythmicity of physiological processes, such as feeding and sleep. The cricket has been employed as a model organism for understanding the neural mechanisms underlying circadian rhythms in insects. However, previous studies measuring rhythm-controlled behaviours only analysed locomotive activity using seesaw-type and infrared sensor-based actometers. Meanwhile, advances in deep learning techniques have made it possible to analyse animal behaviour and posture using software that is devoid of human bias and does not require physical tagging of individual animals. Here, we present a system that can simultaneously quantify multiple behaviours in individual crickets – such as locomotor activity, feeding, and sleep-like states – in the long-term, using DeepLabCut, a supervised machine learning-based software for body keypoints labelling. Our system successfully labelled the six body parts of a single cricket with a high level of confidence and produced reliable data showing the diurnal rhythms of multiple behaviours. Our system also enabled the estimation of sleep-like states by focusing on posture, instead of immobility time, which is a conventional parameter. We anticipate that this system will provide an opportunity for simultaneous and automatic prediction of cricket behaviour and posture, facilitating the study of circadian rhythms.

Machine learning on perovskite photovoltaics reveals the relative importance of material and process information, while data degeneracy limits prediction accuracy.

Abstract

Background

Cerebral organoids are three-dimensional in vitro cultured brains that mimic the function and structure of the human brain. One of the major challenges for cerebral organoids is the lack of functional vasculature. Without perfusable vessels, oxygen and nutrient supplies may be insufficient for long-term culture, hindering the investigation of the neurovascular interactions. Recently, several strategies for the vascularization of human cerebral organoids have been reported. However, the generalizable trends and variability among different strategies are unclear due to the lack of a comprehensive characterization and comparison of these vascularization strategies. In this study, we aimed to explore the effect of different vascularization strategies on the nervous system and vasculature in human cerebral organoids.

Results

We integrated single-cell RNA sequencing data of multiple vascularized and vascular organoids and fetal brains from publicly available datasets and assessed the protocol-dependent and culture-day-dependent effects on the cell composition and transcriptomic profiles in neuronal and vascular cells. We revealed the similarities and uniqueness of multiple vascularization strategies and demonstrated the transcriptomic effects of vascular induction on neuronal and mesodermal-like cell populations. Moreover, our data suggested that the interaction between neurons and mesodermal-like cell populations is important for the cerebrovascular-specific profile of endothelial-like cells.

Conclusions

This study highlights the current challenges to vascularization strategies in human cerebral organoids and offers a benchmark for the future fabrication of vascularized organoids.

Abstract

In recent years, serum‐free medium for mammalian cell cultivation has attracted a lot of attention, considering the high cost of production and environmental load involved in developing the conventional animal sera. The use of alternative growth‐promoting products in mammalian cell cultivation such as extracts from microalgae has proven to be quite beneficial and environmental‐friendly. This research aims to cultivate mammalian cells with growth‐promoting factors derived from Chlorococcum littorale . We have established a simple extraction using the ultrasonication method and applied the extract in place of serum on mammalian C2C12 cell lines, 3T3 cell lines, and CHO cell lines to compare and analyze the effectiveness of the extract. Cell passage was conducted in a suspended culture condition with the addition of the extract. The results indicate that the extract from microalgae shows a high proliferation rate in all cell lines without fetal bovine serum. Moreover, it is eco‐friendly and has huge potential to replace the traditional cell culture system. It could be applied in the fields of regenerative medicine, gene/cell therapies, as well as cultured meat production.

Abstract

Although hollow carbon structures have been extensively studied in recent years, their interior surfaces are not fully utilized due to the lack of fluent porous channels in the closed shell walls. This study presents a tailored design of open‐mouthed particles hollow cobalt/nitrogen‐doped carbon with mesoporous shells (OMH‐Co/NC), which exhibits sufficient accessibility and electroactivity on both the inner and outer surfaces. By leveraging the self‐conglobation effect of metal sulfate in methanol, a raspberry‐structured Zn/Co‐ZIF (R‐Zn/Co‐ZIF) precursor is obtained, which is further carbonized to fabricate the OMH‐Co/NC. In‐depth electrochemical investigations demonstrate that the introduction of open pores can enhance mass transfer and improve the utilization of the inner active sites. Benefiting from its unique structure, the resulting OMH‐Co/NC exhibits exceptional electrocatalytic oxygen reduction performance, achieving a half‐wave potential of 0.865 V and demonstrating excellent durability.

Abstract

The insect gut is colonized by microbes that confer a myriad of beneficial services to the host, including nutritional support, immune enhancement, and even influence behavior. Insect gut microbes show dynamic changes due to the gut compartments, sex, and seasonal and geographic influences. Crickets are omnivorous hemimetabolous insects that have sex-specific roles, such as males producing chirping sounds for communication and exhibiting fighting behavior. However, limited information is available on their gut bacterial communities, hampering studies on functional compartmentalization of the gut and sex-specific roles of the gut microbiota in omnivorous insects. Here, we report a metagenomic analysis of the gut bacteriome of the field cricket Teleogryllus occipitalis using 16S rRNA V3-V4 amplicon sequencing to identify sex- and compartment-dependent influences on its diversity and function. The structure of the gut microbiota is strongly influenced by their gut compartments rather than sex. The species richness and diversity analyses revealed large difference in the bacterial communities between the gut compartments while minor differences were observed between the sexes. Analysis of relative abundance and predicted functions revealed that nitrogen- and oxygen-dependent metabolism and amino acid turnover were subjected to functional compartmentalization in the gut. Comparisons between the sexes revealed differences in the gut microbiota, reflecting efficiency in energy use, including glycolytic and carbohydrate metabolism, suggesting a possible involvement in egg production in females. This study provides insights into the gut compartment dependent and sex-specific roles of host-gut symbiont interactions in crickets and the industrial production of crickets.

Abstract

Multimetallic alloys (MMAs) with various compositions enrich the materials library with increasing diversity and have received much attention in catalysis applications. However, precisely shaping MMAs in mesoporous nanostructures and mapping the distributions of multiple elements remain big challenge due to the different reduction kinetics of various metal precursors and the complexity of crystal growth. Here we design a one-pot wet-chemical reduction approach to synthesize core–shell motif PtPdRhRuCu mesoporous nanospheres (PtPdRhRuCu MMNs) using a diblock copolymer as the soft template. The PtPdRhRuCu MMNs feature adjustable compositions and exposed porous structures rich in highly entropic alloy sites. The formation processes of the mesoporous structures and the reduction and growth kinetics of different metal precursors of PtPdRhRuCu MMNs are revealed. The PtPdRhRuCu MMNs exhibit robust electrocatalytic hydrogen evolution reaction (HER) activities and low overpotentials of 10, 13, and 28 mV at a current density of 10 mA cm⁻² in alkaline (1.0 M KOH), acidic (0.5 M H₂SO₄), and neutral (1.0 M phosphate buffer solution (PBS)) electrolytes, respectively. The accelerated kinetics of the HER in PtPdRhRuCu MMNs are derived from multiple compositions with synergistic interactions among various metal sites and mesoporous structures with excellent mass/electron transportation characteristics.

The solid–solid phase transition in molecular solids can be predicted by positive-unlabeled learning using molecular descriptors.

Abstract

Single crystals of ferroelectric triglycine sulfate doped with glycine analogs serine, threonine, lactic acid, and alaninol were grown via the slow solvent evaporation method. The resulting ferroelectric domain structures and polarization–electric field hysteresis loops revealed that these dopants caused triglycine sulfate to form a multidomain structure. This was attributed to hydrogen bonds not being formed, which is significant in polarization reversal, due to the side chains and the substituents of the dopant molecules. Therefore, the dopants did not affect the surrounding dipoles enough to cause cooperative phenomena, such as dipole‒dipole interactions, and do not result in the formation of a single- domain, unlike alanine in our previous study.

Chiroptics is the study of the changes in circular polarization states of light transmitted through analytes typically dissolved in isotropic solutions. However, experimental challenges have long prevented chiroptical measurements of anisotropic media such as single crystals of low symmetry, liquid crystals, or structured films. The high accuracy universal polarimeter (HAUP) was introduced in 1983 to investigate the differential refraction of left and right circular polarization states, circular birefringence (CB), and even in anisotropic media that are dominated by the differential refraction of orthogonal linear polarization states, linear birefringence (LB). In this century, the HAUP was extended to also measure not only the dispersive optical effects (CB and LB) but also the corresponding dissipative effects, circular dichroism (CD) and linear dichroism (LD), differences in light absorption. The improved device is the generalized-HAUP (G-HAUP). Not only can it deliver all the linear optical properties of dissymmetric, anisotropic, and absorbing media, but it can also do so in the ultraviolet as well as the visible part of the electromagnetic spectrum. In this review, characteristic features of the G-HAUP and its applications to crystals of photomechanical salicylidenephenylethylamines, alanine, benzil, and magneto-optical CeF3 are described.

Molecular crystals have shown remarkable adaptability in response to a range of external stimuli. Here, we survey this emerging field and provide a critical overview of the experimental, computational and instrumental tools being used to design and apply such materials.

Phylogenetic trees provide insight into the evolutionary trajectories of species and molecules. However, because (2n-5)! Phylogenetic trees can be constructed from a dataset containing n sequences, but this method of phylogenetic tree construction is not ideal from the viewpoint of a combinatorial explosion to determine the optimal tree using brute force. Therefore, we developed a method for constructing a phylogenetic tree using a Fujitsu Digital Annealer, a quantum-inspired computer that solves combinatorial optimization problems at a high speed. Specifically, phylogenetic trees are generated by repeating the process of partitioning a set of sequences into two parts (i.e., the graph-cut problem). Here, the optimality of the solution (normalized cut value) obtained by the proposed method was compared with the existing methods using simulated and real data. The simulation dataset contained 32-3200 sequences, and the average branch length according to a normal distribution or the Yule model ranged from 0.125 to 0.750, covering a wide range of sequence diversity. In addition, the statistical information of the dataset is described in terms of two indices: transitivity and average p-distance. As phylogenetic tree construction methods are expected to continue to improve, we believe that this dataset can be used as a reference for comparison and confirmation of the validity of the results. Further interpretation of these analyses is explained in W. Onodera, N. Hara, S. Aoki, T. Asahi, N. Sawamura, Phylogenetic tree reconstruction via graph cut presented using a quantum-inspired computer, Mol. Phylogenet. Evol. 178 (2023) 107636.

Background: The house cricket, Acheta domesticus, is one of the most farmed insects worldwide and the foundation of an emerging industry using insects as a sustainable food source. Edible insects present a promising alternative for protein production amid a plethora of reports on climate change and biodiversity loss largely driven by agriculture. As with other crops, genetic resources are needed to improve crickets for food and other applications. Methods: We present the first high quality annotated genome assembly of A. domesticus from long read data and scaffolded to chromosome level, providing information needed for genetic manipulation. Results: Gene groups related to immunity were annotated and will be useful for improving value to insect farmers. Metagenome scaffolds in the A. domesticus assembly, including Invertebrate Iridescent Virus 6 (IIV6), were submitted as host-associated sequences. We demonstrate both CRISPR/Cas9-mediated knock-in and knock-out of A. domesticus and discuss implications for the food, pharmaceutical, and other industries. RNAi was demonstrated to disrupt the function of the vermilion eye-color gene producing a useful white-eye biomarker phenotype. Conclusions: We are utilizing these data to develop technologies for downstream commercial applications, including more nutritious and disease-resistant crickets, as well as lines producing valuable bioproducts, such as vaccines and antibiotics.

Abstract

The flourishing field of soft robotics requires versatile actuation methodology. Natural vibration is a physical phenomenon that can occur in any material. Here, we report high-speed bending of anisole crystals by natural vibration induced by the photothermal effect. Rod-shaped crystal cantilevers undergo small, fast repetitive bending (~0.2°) due to natural vibration accompanied by large photothermal bending (~1°) under ultraviolet light irradiation. The natural vibration is greatly amplified by resonance upon pulsed light irradiation at the natural frequency to realise high frequency (~700 Hz), large bending (~4°), and high energy conversion efficiency from light to mechanical energy. The natural vibration is induced by the thermal load generated by the temperature gradient in the crystal due to the photothermal effect. The bending behaviour is successfully simulated using finite element analysis. Any light-absorbing crystal can be actuated by photothermally induced natural vibration. This finding of versatile crystal actuation can lead to the development of soft robots with high-speed and high-efficient actuation capabilities.

Spin-state engineering was proposed to enhance the peroxidase-like activity of single-atom nanozymes through the electron-withdrawing properties of Pd nanoclusters, which facilitates the heterolysis process of H ₂ O ₂ and the desorption of H ₂ O.

Phylogenetic trees are essential tools in evolutionary biology that present information on evolutionary events among organisms and molecules. From a dataset of n sequences, a phylogenetic tree of (2n-5)!! possible topologies exists, and determining the optimum topology using brute force is infeasible. Recently, a recursive graph cut on a graph-represented-similarity matrix has proven accurate in reconstructing a phylogenetic tree containing distantly related sequences. However, identifying the optimum graph cut is challenging, and approximate solutions are currently utilized. Here, a phylogenetic tree was reconstructed with an improved graph cut using a quantum-inspired computer, the Fujitsu Digital Annealer (DA), and the algorithm was named the "Normalized-Minimum cut by Digital Annealer (NMcutDA) method". First, a criterion for the graph cut, the normalized cut value, was compared with existing clustering methods. Based on the cut, we verified that the simulated phylogenetic tree could be reconstructed with the highest accuracy when sequences were diverged. Moreover, for some actual data from the structure-based protein classification database, only NMcutDA could cluster sequences into correct superfamilies. Conclusively, NMcutDA reconstructed better phylogenetic trees than those using other methods by optimizing the graph cut. We anticipate that when the diversity of sequences is sufficiently high, NMcutDA can be utilized with high efficiency.

Light driven crystal actuators, where bending direction and speed are controlled by crystal thickness and light wavelength, are fabricated.

Structural and mechanical studies of benzil and oxalate crystals highlight the microscopic and macroscopic basis for the co-existence of orthogonal mechanical traits and the elastic to plastic transformation under different stress settings.

Precise single-crystal structure analyses of the title compound, bis(glycinium) sulfate–glycine (1/1), 2C₂H₆NO₂ ⁺·SO₄ ²⁻·C₂H₅NO₂ (or C₆H₁₇N₃O₁₀S), non-deuterated triglycine sulfate (HTGS) at 20 K and 298 K were undertaken using time-of-flight neutron diffraction data. At 20 K for the O—H...O hydrogen bond between the glycinium cation and the zwitterionic, unprotonated glycine molecule that is associated with the ferroelectric behaviour of HTGS, O—H = 1.070 (3), H...O = 1.408 (3) [δ = 0.338 (4)], O...O = 2.4777 (15) Å and O—H...O = 179.0 (4)°, which is in good agreement with previous studies. Two reasonable structures for the same three atoms were refined for the 298 K dataset. One is a single-minimum potential-energy model, with O—H = 1.090 (12), H...O = 1.361 (12) [δ = 0.271 (17)], O...O = 2.450 (7) Å and O—H...O = 179.2 (10)°, having the H atom with a large ellipticity along the bond path between the O atoms. The other is a double-minimum potential-energy model having two H atom sites with occupancies of 0.876 (8) and 0.124 (8): for the major occupancy component, O—H = 1.065 (12), H...O = 1.387 (12), O...O = 2.451 (7) Å and O—H...O = 178.2 (11)° and for the minor component, O—H = 1.06 (4), H...O = 1.41 (4), O...O = 2.451 (7) Å and O—H...O = 166 (2)°. These models did not show any significant differences in R factors. In addition, the unit-cell parameters and other structural parameters of HTGS did not show any major differences compared to those of partially deuterated TGS and fully deuterated TGS for both 20 K and 298 K.

A CNTs supported amorphous Ni–P alloy NPs catalyst is synthesized by a simple one-pot microwave heating method. The resulting outstanding hydrogenation performance is due to the high-dispersion of Ni–P NPs and the enhanced metal–support interaction.

Recently, cultured meat obtained from livestock-derived cells is being considered as a sustainable food source that reduces the use of natural resources. This study aimed to show that nutrients extracted from Chlorella vulgaris were beneficial in the culture of primary bovine myoblasts (PBMs), a major cell source for cultured meat production. Nutrients (glucose, amino acids, and vitamins) present in the animal-cell culture media were effectively recovered from C. vulgaris using acid hydrolysis treatment. On culture in nutrient-free inorganic salt solution, cell death was induced in most PBMs after 6 days of cultivation. However, the addition of C. vulgaris extract (CVE) significantly improved PBM viability, which was comparable to the viability in conventional culture medium (Dulbecco's modified Eagle's medium). Furthermore, by adding horse serum to induce differentiation, the formation of myotubes was confirmed when CVE were used. Together, the results showed that CVE could be used as an alternative to the conventional culture medium for PBMs. These findings will not only lower the environmental risks associated with the establishment of this eco-friendly cell culture system, but also highlight microalgae as a potent nutrient source that can replace conventional grain-dependent nutrient sources.

Abstract

Significant advances in biophysical methods such as next-generation sequencing technologies have now opened the way to conduct evolutionary and applied research based on the genomic information of greatly diverse insects. Crickets belonging to Orthoptera (Insecta: Polyneoptera), one of the most flourishing groups of insects, have contributed to the development of multiple scientific fields including developmental biology and neuroscience and have been attractive targets in evolutionary ecology for their diverse ecological niches. In addition, crickets have recently gained recognition as food and feed. However, the genomic information underlying their biological basis and application research toward breeding is currently underrepresented. In this review, we summarize the progress of genomics of crickets. First, we outline the phylogenetic position of crickets in insects and then introduce recent studies on cricket genomics and transcriptomics in a variety of fields. Furthermore, we present findings from our analysis of polyneopteran genomes, with a particular focus on their large genome sizes, chromosome number, and repetitive sequences. Finally, how the cricket genome can be beneficial to the food industry is discussed. This review is expected to enhance greater recognition of how important the cricket genomes are to the multiple biological fields and how basic research based on cricket genome information can contribute to tackling global food security.

<title>Abstract</title>Superelasticity is a type of elastic response to an applied external force, caused by a phase transformation. Actuation of materials is also an elastic response to external stimuli such as light and heat. Although both superelasticity and actuation are deformations resulting from stimulus-induced stress, there is a phenomenological difference between the two with respect to whether force is an input or an output. Here, we report that a molecular crystal manifests superelasticity during photo-actuation under light irradiation. The crystal exhibits stepwise twisted actuation due to two effects, photoisomerization and photo-triggered phase transition, and the actuation behavior is simulated based on a dynamic multi-layer model. The simulation, in turn, reveals how the photoisomerization and phase transition progress in the crystal, indicating superelasticity induced by modest stress due to the formation of photoproducts. This work provides not only a successful simulation of stepwise twisted actuation, but also to the best of our knowledge the first indication of superelasticity induced by light.

Abstract

Species of infraorder Gryllidea, or crickets, are useful invertebrate models for studying developmental biology and neuroscience. They have also attracted attention as alternative protein sources for human food and animal feed. Mitochondrial genomic information on related invertebrates, such as katydids, and locusts, has recently become available in attempt to clarify the controversial classification schemes, although robust phylogenetic relationships with emphasis on crickets remain elusive. Here, we report newly sequenced complete mitochondrial genomes of crickets to study their phylogeny, genomic rearrangements, and adaptive evolution. First, we conducted de novo assembly of mitochondrial genomes from eight cricket species and annotated protein-coding genes and transfer and ribosomal RNAs using automatic annotations and manual curation. Next, by combining newly described protein-coding genes with public data of the complete Gryllidea genomes and gene annotations, we performed phylogenetic analysis and found gene order rearrangements in several branches. We further analyzed genetic signatures of selection in ant-loving crickets (Myrmecophilidae), which are small wingless crickets that inhabit ant nests. Three distinct approaches revealed two positively selected sites in the cox1 gene in these crickets. Protein 3D structural analyses suggested that these selected sites could influence the interaction of respiratory complex proteins, conferring benefits to ant-loving crickets with a unique ecological niche and morphology. These findings enhance our understanding of the genetic basis of cricket evolution without relying on estimates based on a limited number of molecular markers.

Amyloid precursor protein (APP) family members are involved in essential neuronal development including neurite outgrowth, neuronal migration and maturation of synapse and neuromuscular junction. Among the APP gene family members, amyloid precursor-like protein 1 (APLP1) is selectively expressed in neurons and has specialized functions during synaptogenesis. Although a potential role for APLP1 in neuronal evolution has been indicated, its precise evolutionary and functional contributions are unknown. This study shows the molecular evolution of the vertebrate APP family based on phylogenetic analysis, while contrasting the evolutionary differences within the APP family. Phylogenetic analysis showed 15 times higher substitution rate that is driven by positive selection at the stem branch of the mammalian APLP1, resulting in dissimilar protein sequences compared to APP/APLP2. Docking simulation identified one positively selected site in APLP1 that alters the heparin-binding site, which could affect its function, and dimerization rate. Furthermore, the evolutionary rate covariation between the mammalian APP family and synaptic adhesion molecules (SAMs) was confirmed, indicating that only APLP1 has evolved to gain synaptic adhesion property. Overall, our results suggest that the enhanced synaptogenesis property of APLP1 as one of the SAMs may have played a role in mammalian brain evolution.

<p>In asymmetric autocatalysis with amplification of ee, molecular chirality of highly enantioenriched organic compounds is controlled by a crystal TGS, whose chirality is switchable by changing the direction of the applied static electric field.</p>

Recently, soft robots, which are made of soft and light organic materials, have attracted much attention because of improved safety for daily interactions with humans. Mechanically responsive materials that can move macroscopically by external stimuli, such as light and heat, have been studied extensively over the past two decades, and they are expected to be applicable to soft robots. Among them, mechanically responsive crystals are attractive in terms of a larger Young’s modulus and faster response speed compared with polymers and gels. However, it is impractical to use one piece of a single crystal as a crystal machine; it is difficult to control the size of crystals and obtain large crystals. Hybridization of crystals with polymers is one way to create actuators with more realistic movements. Herein, we report a hybrid crystal assembly in which plate-like salicylideneaniline crystals are aligned in polymer films by a “rubbing” technique, a new approach which is inexpensive, easy, and applicable to a wide range of crystals and polymers. The hybrid films bent reversibly upon alternate irradiation with ultraviolet and visible light. The hybrid films bent as fast as single crystals, even when larger than single-crystal size, showing great mechanical performance originating from the advantages of both molecular crystals (fast response time) and polymers (large size). This work enriches the development of light-driven hybrid actuators composed of molecular crystals and polymers.

Abstract

Research using X-ray diffraction (XRD) remains to be accelerated in spite of its importance in materials science. Automated noise separation or optimization of measurement time in XRD is beneficial for discovering materials. This study analyzes two-dimensional XRD (2D-XRD) with density-based clustering to accelerate XRD. This clustering technique can separate diffraction pattern signals from noises, even with low signal-to-noise ratio (S/N) 2D-XRD. Moreover, we found that the crystalline degree information in composition spreads is captured based on density. This information requires a long time to be captured with conventional one-dimensional detectors or scintillation counters. Therefore, these findings lead to dramatic reduction and optimization of measurement time to improve S/N. The proposed procedure is applicable with 2D detector measurements.

<p>The bending deflection and blocking force of photo-bending crystals of different sizes were experimentally measured at various light intensities, and then modeled by the machine learning-based regression.</p>

Abstract

Selective hydrogenation of nitriles is an industrially relevant synthetic route for the preparation of primary amines. Amorphous metal–boron alloys have a tunable, glass‐like structure that generates a high concentration of unsaturated metal surface atoms that serve as active sites in hydrogenation reactions. Here, a method to create nanoparticles composed of mesoporous 3D networks of amorphous nickel–boron (Ni‐B) alloy is reported. The hydrogenation of benzyl cyanide to β‐phenylethylamine is used as a model reaction to assess catalytic performance. The mesoporous Ni‐B alloy spheres have a turnover frequency value of 11.6 h⁻¹, which outperforms non‐porous Ni‐B spheres with the same composition. The bottom‐up synthesis of mesoporous transition metal–metalloid alloys expands the possible reactions that these metal architectures can perform while simultaneously incorporating more Earth‐abundant catalysts.

Cereblon (CRBN) was identified as a gene that causes intellectual disabilities. The encoded CRBN protein, containing 442 amino acids, is located in several organs. Cytosolic CRBN was reported to mainly act as a component of the E3 ubiquitin ligase complex. CRBN is one of the substrate receptors of the E3 ubiquitin ligase complex and promotes the degradation of targeted proteins. Studies have reported that CRBN recognizes the C-terminal region of the amyloid precursor protein (APP), a protein known for its involvement in the development of Alzheimer's disease. Although CRBN may interact with the C-terminal region of APP in mice, the CRBN-mediated degradation mechanism of human APP remains unclear. Here, we analyzed the CRBN-mediated degradation mechanism of human APP via the ubiquitin-proteasome system. Immunoprecipitation experiments showed that CRBN interacts with human full-length APP via its C-terminal region. Next, we examined CRBN-mediated degradation of APP in the ubiquitin-proteasome system. CRBN recognizes Lys751 in human APP and ubiquitinates it in SH-SY5Y cells. Overexpression of CRBN decreased wild-type APP expression levels. In contrast, the expression level of K751R APP remained unchanged by CRBN overexpression, while knockdown of endogenous CRBN increased APP levels. As such, our results suggest that CRBN ubiquitinates Lys751 of human APP thereby degrading it via the ubiquitin-proteasome system.

ABSTRACT

Mitochondrial autophagy (mitophagy) is an essential and evolutionarily conserved process that maintains mitochondrial integrity via the removal of damaged or superfluous mitochondria in eukaryotic cells. Phosphatase and tensin homolog (PTEN)-induced putative kinase 1 (PINK1) and Parkin promote mitophagy and function in a common signaling pathway. PINK1-mediated ubiquitin phosphorylation at Serine 65 (Ser65-pUb) is a key event in the efficient execution of PINK1/Parkin-dependent mitophagy. However, few studies have used immunohistochemistry to analyze Ser65-pUb in the mouse. Here, we examined the immunohistochemical characteristics of Ser65-pUb in the mouse hippocampus. Some hippocampal cells were Ser65-pUb positive, whereas the remaining cells expressed no or low levels of Ser65-pUb. PINK1 deficiency resulted in a decrease in the density of Ser65-pUb-positive cells, consistent with a previous hypothesis based on in vitro research. Interestingly, Ser65-pUb-positive cells were detected in hippocampi lacking PINK1 expression. The CA3 pyramidal cell layer and the dentate gyrus (DG) granule cell layer exhibited significant reductions in the density of Ser65-pUb-positive cells in PINK1-deficient mice. Moreover, Ser65-pUb immunoreactivity colocalized predominantly with neuronal markers. These findings suggest that Ser65-pUb may serve as a biomarker of in situ PINK1 signaling in the mouse hippocampus; however, the results should be interpreted with caution, as PINK1 deficiency downregulated Ser65-pUb only partially.

Thalidomide was originally used as a sedative and found to be a teratogen, but now thalidomide and its derivatives are widely used to treat haematologic malignancies. Accumulated evidence suggests that thalidomide suppresses nerve cell death in neurologic model mice. However, detailed molecular mechanisms are unknown. Here we examined the molecular mechanism of thalidomide's neuroprotective effects, focusing on its target protein, cereblon (CRBN), and its binding protein, AMP-activated protein kinase (AMPK), which plays an important role in maintaining intracellular energy homeostasis in the brain. We used a cerebral ischemia rat model of middle cerebral artery occlusion/reperfusion (MCAO/R). Thalidomide treatment significantly decreased the infarct volume and neurological deficits of MCAO/R rats. AMPK was the key signalling protein in this mechanism. Furthermore, we considered that the AMPK-CRBN interaction was altered when neuroprotective action by thalidomide occurred in cells under ischemic conditions. Binding was strong between AMPK and CRBN in normal SH-SY5Y cells, but was weakened by the addition of H2O2. However, when thalidomide was administered at the same time as H2O2, the binding of AMPK and CRBN was partly restored. These results suggest that thalidomide inhibits the activity of AMPK via CRBN under oxidative stress and suppresses nerve cell death.

Consolidation of Sm2Fe17N3 powder with a new Sm-based alloy as a metal binder was examined. Investigation of various Sm-based alloys led to the discovery of a Sm-Fe-Cu-Al alloy having a low melting point of 495 °C, which is more than 100 °C lower than the thermal decomposition temperature of Sm2Fe17N3. The metallographic structure of the Sm-Fe-Cu-Al alloy ingot was a SmCu/Sm eutectic structure containing solid-solution Fe, Cu and Al. Pulverized Sm-Fe-Cu-Al powder as a binder was mixed with Sm2Fe17N3 powder, and the mixture was hot-pressed by a current sintering apparatus. The Sm-Fe-Cu-Al alloy binder did not affect the magnetization of Sm2Fe17N3 adversely after consolidation. The binder-added Sm2Fe17N3 hot-pressed compacts successfully maintained the coercivity of the raw powder over a wide range of hot-pressing temperatures, whereas additive-free Sm2Fe17N3 hot-pressed compacts showed a significant decrease in coercivity. Therefore, the Sm-Fe-Cu-Al alloy binder overcame the weakest point of Sm2Fe17N3 magnets. XRD analysis suggested that the Sm-Fe-Cu-Al binder restrained precipitation of the α-Fe phase, which is thought to be the probable cause the decrease of coercivity.

:Ge-132 is a synthetic organic germanium that is used as a dietary supplement. The antioxidant activity of Ge-132 on cultured mammalian cells was investigated in this study. First, Ge-132 cytotoxicity on mammalian cultured cells was determined by measuring lactate dehydrogenase (LDH) levels. Ge-132 had no cytotoxic effect on three different cell lines. Second, the cell proliferative effect of Ge-132 was determined by measuring ATP content of whole cells and counting them. Ge-132 treatment of CHO-K1 and SH-SY5Y cells promoted cell proliferation in a dose-dependent manner. Finally, antioxidant activity of Ge-132 against hydrogen peroxide-induced oxidative stress was determined by measuring the levels of intracellular reactive oxygen species (ROS) and carbonylated proteins. Pre-incubation of CHO-K1 and SH-SY5Y cells with Ge-132 suppressed intracellular ROS production and carbonylated protein levels induced by hydrogen peroxide. Our results suggest that Ge-132 has antioxidant activity against hydrogen peroxide-induced oxidative stress.

UnaG is a green-emitting fluorescent protein that utilizes unconjugated bilirubin (BR) as its fluorophore. While BR has captured the attention of physiologists as an important antioxidant that scavenges reactive oxygen species in biological membranes, its excessive accumulation causes several clinical symptoms. Although the optimal regulation of BR concentration would result in clinical therapies for aging as well as reduce risks of clinical symptoms, UnaG hardly releases BR owing to its extremely high affinity for BR (Kd = 98 pM). Herein, we engineered the BR binding and fluorescence of UnaG to be Ca2+-sensitive via a genetic insertion of calmodulin (CaM). The resultant UnaG/CaM hybrid protein is a dual-ligand modulable fluorescent protein
binding of the fluorogenic ligand BR is negatively regulated by the other ligand, Ca2+ ion. The affinity for BR differed by three orders of magnitude between the Ca2+-free state (Kd = 9.70 nM) and Ca2+-saturated state (Kd = 9.65 μM). The chimeric protein can release nano- to micro-molar levels of BR with Ca2+ control, and is thus named BReleaCa (BR + releaser + Ca2+). Such a protein hybridization technique will be generally applicable to change the ligand binding properties of a variety of ligand-inducible functional proteins.

The mechanical motion of materials has been increasingly explored in terms of bending and expansion/contraction. However, the locomotion of materials has been limited. Here, we report walking and rolling locomotion of chiral azobenzene crystals, induced thermally by a reversible single-crystal-to-single-crystal phase transition. Long plate-like crystals with thickness gradient in the longitudinal direction walk slowly, like an inchworm, by repeated bending and straightening under heating and cooling cycles near the transition temperature. Furthermore, thinner, longer plate-like crystals with width gradient roll much faster by tilted bending and then flipping under only one process of heating or cooling. The length of the crystal is shortened above the transition temperature, which induces bending due to the temperature gradient to the thickness direction. The bending motion is necessarily converted to the walking and rolling locomotion due to the unsymmetrical shape of the crystal. This finding of the crystal locomotion can lead to a field of crystal robotics.

<p> Stable mesoporous nickel (Ni) films can be prepared using polystyrene- b -poly-(oxyethylene) (PS- b -PEO) micelles as sacrificial templates. </p>

UnaG is a recently discovered ligand-induced fluorescent protein that utilizes bound bilirubin (BR) as its fluorophore. The fluorescence of the UnaG-BR complex (holoUnaG) compares in quantum efficiency to that of enhanced green fluorescent protein, but it is superior in that the fluorophore formation is instantaneous and not dependent on oxygen; hence, much attention has been paid to UnaG as a new fluorescent probe. However, many important molecular properties of fluorescent probes remain unknown, such as the association/dissociation rates of BR, which determine the stability thereof, and the dispersibility of UnaG in aqueous solutions, which influence the functions of labeled proteins. In this study, we found, in the process of investigating the association rate, that the holoUnaG takes two distinct fluorescence states, which we named holoUnaG(1) and holoUnaG(2). The holoUnaG(1) initially forms after binding BR and then changes to the brighter holoUnaG(2) by a reversible intra-molecular reaction, thereby finally reaching an equilibrium between the two states. Spectroscopic analysis indicated that the intra-molecular reaction was associated not with a chemical change of BR but with a change in the environmental conditions surrounding BR. We also revealed that the molecular brightness ratio and equilibrium population ratio of the two states (holoUnaG(1)/holoUnaG(2)) were 1:3.9 and 6:4, respectively, using photon number counting analysis. From these results, we have suggested a novel schema, to our knowledge, for the formation of the UnaG and BR complex system and have determined the various rate constants associated therein. Additionally, using analytical ultracentrifugation, we established that UnaG in the apo-state (apoUnaG) and the holoUnaG are monomeric in aqueous solution. These findings provide not only key information for the practical use of UnaG as a fluorescent probe, but also the possibility for development of a brighter UnaG mutant by genetic engineering to constitutive holoUnaG(2).

Optical activity (OA) along the optic axis of crystalline benzil has been measured by many over the past 150 years. However, the OA anisotropy remains uncharacterized due to difficulties in sample preparation as well as competition with linear birefringence (LB). The challenges associated with measuring OA along low-symmetry directions in crystals have too often left scientists with only average values of nonresonant OA in solution, i.e., specific rotations, which continue to resist interpretation in terms of structure. Measuring OA anisotropy has been facilitated by recent advances in polarimetry and optical modeling and here we compare results from two distinct division-of-time polarimeters. The absolute structure of crystalline benzil was established for the first time. The optical rotation (OR) of (+)-crystalline benzil (space group P3(1)21) perpendicular to the optic axis at the sodium D-line is -24.6 +/- 1.1 degrees/mm. A spectroscopic optical model in the transparent region of the crystal is provided. Electronic structure calculations of OR inform the polarimetric measurements and point to the necessity of developing linear response theory with periodic boundary conditions in order to interpret the results of chiroptical measurements in crystals.

Sensing technology for biomolecules has played a key role for maintaining a high quality of life. Various kinds of sensing techniques have been developed for detecting biomolecules. Among the detection techniques which have been reported so far, non-enzymatic glucose detection, based on electrochemical mechanisms, has attracted great interest as a facile route for monitoring glucose levels in the blood. In this method, designing nanostructured electrodes is a promising strategy to improve detection performance. Owing to their fascinating physicochemical properties, including superior electrical and electrocatalytic properties, mesoporous metal films offer a wide range of useful applications which cannot be achieved by other mesoporous materials. In this work, mesoporous Au films (MpGFs) are synthesized by an effective and simple electrochemical process in the presence of a surfactant, where the mesoporous structure can be controlled by the size of the polymeric micelles. The micelles are removed using a tetrahydrofuran-based solvent-extraction method. The activity of MpGFs towards glucose oxidation is evaluated under a fixed potential in alkaline solution. Under optimal potentials, the current response for other interfering molecules is minimal, while the current response for glucose is maximal. A linear relationship between the current response and the glucose content is observed over a wide range of concentrations. Thus, our MpGF shows an excellent performance for electrochemical glucose sensing applications.

We previously succeeded to prepare stable mesoporous Cu films on Au-coated conductive working electrodes by using polystyrene-b-poly(oxyethylene) (PS63000-b-PEO26000) micelles as template and sulfuric acid to increase ionic conductivity. In the present study, we report the preparation of mesoporous Cu films on Cu foil. By changing the Cu salts and electrodeposition potentials, we discuss how these parameters influence the final product. Without having to filtrate interefering species, such as uric acid, ascorbic acid and glucose, the dopamine concentration can be precisely determined by applying a suitable potential. Therefore, non-invasive electrochemical sensing based on mesoporous films will be useful for daily diagnosis of mental disorder.

Mesoporous metals that combine catalytic activity and high surface area can provide more opportunities for electrochemical applications. Various synthetic methods, including hard and soft templating, have been developed to prepare mesoporous/nanoporous metals. Micelle assembly, typically involved in soft-templates, is flexible and convenient for such purposes. It is, however, difficult to control, and the ordering is significantly destroyed during the metal deposition process, which is detrimental when it comes to designing precisely mesostructured materials. In the present work, mesoporous Pd films were uniformly electrodeposited using a nonionic surfactant, triblock copolymer poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide), as a pore-directing agent. The interaction between micelles and metal precursors greatly influences the metal growth and determines the final structure. The water-coordinated species interact with the ethylene oxide moiety of the micelles to effectively drive the Pd(II) species toward the working electrode surface. From small-angle neutron scattering data, it is found that spherical P123 micelles, with an average diameter of similar to 14 nm, are formed in the electrolyte, and the addition of Pd ions does not significantly modify their structure, which is the essence of the micelle assembly approach. The uniformly sized mesopores are formed over the entire mesoporous Pd film and have an average pore diameter of 10.9 nm. Cross-sectional observation of the film also shows mesopores spanning continuously from the bottom to the top of the film. The crystallinity, crystal phase, and electronic coordination state of the Pd film are also confirmed. Through this study, it is found that the optimized surfactant concentration and applied deposition potential are the key factors to govern the formation of homogeneous and well-distributed pores over the entire film. Interestingly, the as-prepared mesoporous Pd films exhibit superior electrocatalytic activity toward the ethanol oxidation reaction by fully utilising the accessible active surface area. Our approach combines electrochemistry with colloidal and coordination chemistry and is widely applicable to other promising metals and alloy electrocatalysts.

Mesoporous Pd@Pt nanoparticles possess high surface areas while still maintaining electroconductivity and low potential for agglomeration. By introducing L-or D-DOPA (3,4-dihydroxyphe-nylalanine) enantiomers during the synthesis of the mesoporous Pd@Pt nanoparticles, we can create a Pt shell that is sensitive to the chirality of the DOPA molecule. We demonstrate sensitive electrochemical detection of DOPA enantiomers.

© 2017 Wiley Periodicals, Inc. Enantiomeric thalidomide undergoes various kinds of biotransformations including chiral inversion, hydrolysis, and enzymatic oxidation, which results in several metabolites, thereby adding to the complexity in the understanding of the nature of thalidomide. To decipher this complexity, we analyzed the multidimensional metabolic reaction networks of thalidomide and related molecules in vitro. Characteristic patterns in the amount of various metabolites of thalidomide and related molecules generated during a combination of chiral inversion, hydrolysis, and hydroxylation were observed using liquid chromatography–tandem mass spectrometry and chiroptical spectroscopy. We found that monosubstituted thalidomide derivatives exhibited different time-dependent metabolic patterns compared with thalidomide. We also revealed that monohydrolyzed and monohydroxylated metabolites of thalidomide were likely to generate mainly by a C-5 oxidation of thalidomide and subsequent ring opening of the hydroxylated metabolite. Since chirality was conserved in most of these metabolites during metabolism, they had the same chirality as that of nonmetabolized thalidomide. Our findings will contribute toward understanding the significant pharmacological effects of the multiple metabolites of thalidomide and its derivatives.

Wavelength dependence measurements of the chiroptical properties in alanine crystals have so far been unsuccessful using conventional spectroscopic techniques. We describe our attempts to measure the wavelength dependence of the optical activity in L- and D-alanine crystals along each crystallographic axis, and to determine the absolute chirality of alanine crystals by correlating the absolute structure to the optical activity using an x-ray diffractometer and a generalized high accuracy universal polarimeter. We have succeeded in accurately measuring the optical rotatory dispersion in the &lt; 010 &gt; direction, which shows that the optical rotation of the n-alanine crystal is dextrorotatory and that of the L-alanine crystal is laevorotatory, thereby determining the absolute chirality. Furthermore, comparison with the optical activity in solution shows that the optical activity in alanine crystals is different not only in value, but also in the sign. These results have led us to conclude that the optical rotatory power in the crystalline state should not be simply the summation of molecular optical rotatory power values. We propose the necessity of a theory, which contains the contribution of molecular interactions within the crystal, in order to calculate the optical rotatory power of the crystalline state.

A fast, high-accuracy universal polarimeter was developed using a charge-coupled device (CCD) spectrometer (CCD-HAUP), to carry out simultaneous optical anisotropic (linear birefringence, LB; linear dichroism, LD) and chiroptical (circular birefringence, CB; circular dichroism, CD) measurements on single crystals without any pretreatment, in the visible region between 400-680 nm. The principle of the HAUP method is to measure the intensities of emergent light passing through a polarizer, a crystal sample, and then an analyzer, as the azimuth angles of the polarizer and analyzer are independently altered. The CCD-HAUP has the unique feature that white transmitted light intensity can be measured using a CCD spectrometer, compared with the generalized HAUP (G-HAUP) system in which monochromatic transmitted light is measured using a photomultiplier. The CCD-HAUP measurements across the entire wavelength region are completed within the G-HAUP measurement time for a single wavelength. The CCD-HAUP drastically reduces the measurement time for a dataset to only 1.5 h, from the 24 h required for the G-HAUP system. LB, LD, CB, and CD measurements of single crystals of alpha-quartz and enantiomeric photomechanical sali-cylidenephenylethylamines before, during, and after ultraviolet light irradiation show results comparable to those obtained using the G-HAUP system. The newly developed system is very effective for samples susceptible to degradation induced by external stimuli, such as light and heat. (C) 2017 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license.

:Amyloid β protein (Aβ) plays a central role in Alzheimer&#039;s disease (AD) pathogenesis. Point mutations in the Aβ sequence, which cluster around the central hydrophobic core of the peptide, are associated with familial AD (FAD). Several mutations have been identified, with the Arctic mutation exhibiting a purely cognitive phenotype that is typical of AD. Our previous findings suggest that Arctic Aβ40 binds to and aggregates with CHRNA7, thereby inhibiting the calcium response and signaling pathways downstream of the receptor. Activation of CHRNA7 is neuroprotective both in vitro and in vivo. Therefore, in the present study, we investigated whether Arctic Aβ40 affects neuronal survival and/or death via CHRNA7. Using human neuroblastoma SH-SY5Y cells, we found that the neuroprotective function of CHRNA7 is blocked by CHRNA7 knockdown using RNA interference. Furthermore, Arctic Aβ40 blocked the neuroprotective effect of nicotine by inhibiting the ERK1/2 pathway downstream of CHRNA7. Moreover, we show that ERK1/2 activation mediates the neuroprotective effect of nicotine against oxidative stress. Collectively, our findings further our understanding of the molecular pathogenesis

The chiral crystal of enantiomeric (S)-N-3,5-di-tert-butylsalicylidene-1-phenylethylamine in the enol form [enol-(S)-1] undergoes a reversible single-crystal-to-single-crystal (SCSC) phase transition at T-c approximate to 3 degrees C from the room temperature beta-form in orthorhombic space group P2(1)2(1)2(1) (Z' = 1) to the low temperature -form in the monoclinic space group P2(1) (Z' = 2) with a thermal hysteresis of approximately 1.7 degrees C. A detailed comparison of the crystal structures of the alpha- and beta-forms revealed that the 5-tert-butyl group of one molecule in the asymmetric unit of the beta-form rotated by ca. 60 degrees, and the dihedral angle between the phenyl and salicyl planes increased slightly in the beta-form crystal. However, the changes in the molecular conformation and packing arrangement are small, which leads to the reversible SCSC phase transition with no destruction of the crystal lattice. The dielectric constant along the b-axis was small, probably due to the weak intermolecular interactions in the crystals.

Cereblon (CRBN) is a substrate receptor of the E3 ubiquitin ligase complex that is highly conserved in animals and plants. CRBN proteins have been implicated in various biological processes such as development, metabolism, learning, and memory formation, and their impairment has been linked to autosomal recessive non-syndromic intellectual disability and cancer. Furthermore, human CRBN was identified as the primary target of thalidomide teratogenicity. Data on functional analysis of CRBN family members in vivo, however, are still scarce. Here we identify Ohgata (OHGT), the Drosophila ortholog of CRBN, as a regulator of insulin signaling-mediated growth. Using ohgt mutants that we generated by targeted mutagenesis, we show that its loss results in increased body weight and organ size without changes of the body proportions. We demonstrate that ohgt knockdown in the fat body, an organ analogous to mammalian liver and adipose tissue, phenocopies the growth phenotypes. We further show that overgrowth is due to an elevation of insulin signaling in ohgt mutants and to the down-regulation of inhibitory cofactors of circulating Drosophila insulin-like peptides (DILPs), named acid-labile subunit and imaginal morphogenesis protein-late 2. The two inhibitory proteins were previously shown to be components of a heterotrimeric complex with growth-promoting DILP2 and DILP5. Our study reveals OHGT as a novel regulator of insulin-dependent organismic growth in Drosophila.

Cereblon (CRBN) is a substrate receptor of the E3 ubiquitin ligase complex that is highly conserved in animals and plants. CRBN proteins have been implicated in various biological processes such as development, metabolism, learning, and memory formation, and their impairment has been linked to autosomal recessive non-syndromic intellectual disability and cancer. Furthermore, human CRBN was identified as the primary target of thalidomide teratogenicity. Data on functional analysis of CRBN family members in vivo, however, are still scarce. Here we identify Ohgata (OHGT), the Drosophila ortholog of CRBN, as a regulator of insulin signaling-mediated growth. Using ohgt mutants that we generated by targeted mutagenesis, we show that its loss results in increased body weight and organ size without changes of the body proportions. We demonstrate that ohgt knockdown in the fat body, an organ analogous to mammalian liver and adipose tissue, phenocopies the growth phenotypes. We further show that overgrowth is due to an elevation of insulin signaling in ohgt mutants and to the down-regulation of inhibitory cofactors of circulating Drosophila insulin-like peptides (DILPs), named acid-labile subunit and imaginal morphogenesis protein-late 2. The two inhibitory proteins were previously shown to be components of a heterotrimeric complex with growth-promoting DILP2 and DILP5. Our study reveals OHGT as a novel regulator of insulin-dependent organismic growth in Drosophila.

Introducing chirality into photomechanical crystals is beneficial for the diversification of mechanical motion. Measurement of the chiroptical and optical anisotropic properties of chiral crystals is indispensable for evaluating photomechanical crystals. The platelike crystals of S- and R-enantiomers of photochromic N-3,5-di-tert-butylsalicylidene-1-phenylethylamine in enol form (enol-(S)-1 and enol-(R)-1) caused bending motion with twisting upon ultraviolet (UV) light irradiation, due to shrinkage along the length and width directions of the irradiated surface, based on the optimized crystal structure of the photoisomerized trans-keto-(S)-1. By employing the generalized high-accuracy universal polarimeter (G-HAUP), optical anisotropic (linear birefringence, LB; linear dichroism, LD) as well as chiroptical (circular birefringence, CB; circular dichroism, CD) spectra of both the enantiomeric crystals on the (001) face were simultaneously measured before and under continuous UV irradiation. The LD peak was observed at 330 nm in the negative sign, derived from the pi-pi* transition of the intramolecularly hydrogen-bonded salicylidenimino moiety. The CD spectra of the S and R crystals revealed the negative and positive Cotton effect at 330 nm, respectively, and new peaks appeared at 460 rim under UV light irradiation due to photoisomerization to the S and R trans-keto isomers at around 10% conversion. The CB and CD spectra evaluated by the HAUP measurement were opposite to those measured in the hexane solution, as well as those simulated by quantum chemical calculation. The dissymmetry parameter, g, of the enol-(S)-1 crystal along the c axis (0.013) was approximately 10 times larger than the g values in the solution (0.0010) and by calculation (0.0016).

Solid-state photochemical reactions in crystals, known as topochemical reactions, are solvent-free green chemical reactions that produce stereospecific molecules. The photoreaction of thymine is interesting because the dimeric photoproduct can form four types of stereoisomers and when the dimer is formed in DNA helices it can cause skin cancers. We investigated the photoreaction of five multisubstituted thymine derivatives in the solid-state, which were designed with crystal engineering concepts to promote pi-pi stacking of benzene rings in the crystal. Powder X-ray diffraction analysis revealed that a para-substituted bis-thymine derivative was aligned along the c axis in the crystal and was susceptible to topochemical reaction to form a polymer, as previously reported. Ortho- and meta-substituted bis-thymine derivatives and a tetrakis-substituted derivative were found to be topochemically unreactive using both gel permeation chromatography (GPC) and X-ray crystal structural analysis. The tris-substituted thymine derivative was found to be topochemically reactive due to favorable crystal packing, which included ethanol molecules to form hydrogen bonding with one of the thymine moieties and stabilize the crystal packing. GPC and crystal structural analysis revealed that it could form tetramer at most via topochemical [2+2]-cycloaddition upon UV irradiation. Based on the crystal structure of the tris-substituted thymine derivative, the structure of the tetrameric photoproduct is expected to link via cis-syn, trans-anti and cis-syn cyclobutane isomers.

The gene coding cereblon (CRBN) was originally identified in genetic linkage analysis of mild autosomal recessive nonsyndromic intellectual disability. CRBN has broad localization in both the cytoplasm and nucleus. However, the significance of nuclear CRBN remains unknown. In the present study, we aimed to elucidate the role of CRBN in the nucleus. First, we generated a series of CRBN deletion mutants and determined the regions responsible for the nuclear localization. Only CRBN protein lacking the N-terminal region was localized outside of the nucleus, suggesting that the N-terminal region is important for its nuclear localization. CRBN was also identified as a thalidomide-binding protein and component of the cullin-4-containing E3 ubiquitin ligase complex. Thalidomide has been reported to be involved in the regulation of the transcription factor Ikaros by CRBN-mediated degradation. To investigate the nuclear functions of CRBN, we performed co-immunoprecipitation experiments and evaluated the binding of CRBN to Ikaros. As a result, we found that CRBN was associated with Ikaros protein, and the N-terminal region of CRBN was required for Ikaros binding. In luciferase reporter gene experiments, CRBN modulated transcriptional activity of Ikaros. Furthermore, we found that CRBN modulated Ikaros-mediated transcriptional repression of the proenkephalin gene by binding to its promoter region. These results suggest that CRBN binds to Ikaros via its N-terminal region and regulates transcriptional activities of Ikaros and its downstream target, enkephalin. (C) 2016 Elsevier Inc. All rights reserved.

Lon protease plays a major role in the protein quality control system in mammalian cell mitochondria. It is present in the mitochondrial matrix, and degrades oxidized and misfolded proteins, thereby protecting the cell from various extracellular stresses, including oxidative stress. The intellectual disability-associated and thalidomide-binding protein cereblon (CRBN) contains a large, highly conserved Lon domain. However, whether CRBN has Lon protease-like function remains unknown. Here, we determined if CRBN has a protective function against oxidative stress, similar to Lon protease. We report that CRBN partially distributes in mitochondria, suggesting it has a mitochondrial function. To specify the mitochondrial role of CRBN, we mitochondrially expressed CRBN in human neuroblastoma SH-SY5Y cells. The resulting stable SH-SY5Y cell line showed no apparent effect on the mitochondrial functions of fusion, fission, and membrane potential. However, mitochondrially expressed CRBN exhibited protease activity, and was induced by oxidative stress. In addition, stably expressed cells exhibited suppressed neuronal cell death induced by hydrogen peroxide. These results suggest that CRBN functions specifically as a Lon-type protease in mitochondria.

The photomechanical motion of chiral crystals of trans-azobenzene derivatives with an (S)- and (R)-phenylethylamide group was investigated and compared with a racemic crystal. Changes in the UV/Vis absorption spectra of the powdered crystals before and after UV irradiation were measured by using an optical waveguide spectrometer, showing that the lifetime of the cis-to-trans thermal backisomerization of the chiral crystals was faster than that of the racemic crystals. Upon UV irradiation, a long plate-like chiral microcrystal bent away from the light source with a twisting motion. A square-like chiral microcrystal curled toward the light with some twisting. Reversible bending of a rod-like chiral microcrystal was repeatable over twenty-five cycles. In contrast, bending of a plate-like racemic microcrystal was small. A possible mechanism for the bending and twisting motion was discussed based on the optimized cis conformer determined by using calculations, showing that the bending motion with twisting is caused by elongation along the b axis and shrinkage along the a axis.

Upon microwave irradiation, esterification of octanoic acid with 1-octanol in the presence of hydrochloric acid as an acid catalyst proceeded more efficiently in glass vessels than in silicon carbide (SiC) vessels, affording 1-octyl octanoate in higher yields and revealing microwave effects during esterification.

Achiral benzophenone is one of the simplest organic aromatic ketones that crystallize in the chiral form. The absolute structure of chiral crystals consisting of achiral benzophenone was firstly determined with single-crystal X-ray diffraction analysis and the absolute structure was successfully correlated with the solid-state circular dichroism spectra.

Achiral benzophenone is one of the simplest organic aromatic ketones that crystallize in the chiral form. The absolute structure of chiral crystals consisting of achiral benzophenone was firstly determined with single-crystal X-ray diffraction analysis and the absolute structure was successfully correlated with the solid-state circular dichroism spectra.

Polymer crystallization affects structural and mechanical properties of polymer thin films. In this study, we focused on the thermal annealing-induced crystallization in semi-crystalline poly(l-lactic acid) (PLLA) ultrathin films (referred as nanosheets) was investigated in terms of interfacial interaction of PLLA with air and substrate. The surface structure of the PLLA nanosheets observed by atomic force microscopy showed that roughness of the air-side surface increased due to crystallization of PLLA under thermal annealing, whereas that of the substrate-side surface changed little. The elastic moduli and the physical adhesiveness of the nanosheets also changed only on the surface of the air side from crystallization, in contrast to the substrate side. The X-ray diffraction studies of the PLLA nanosheets with different thickness showed that the crystalline contents steeply increased below ca. 200 nm. These results indicated that the crystallization was enhanced near the surface of the air side and restricted near that of the substrate side due to the different interfacial association of the polymer chains in the nanosheet.

The photomechanical bending of crystals of a stilbene-type compound substituted with anthracene and indanone groups, (E)-2-(9-anthrylmethylene)-1-indanone (trans-1), was investigated. When a narrow plate-like microcrystal was irradiated with ultraviolet (UV) light at 365 nm, the crystal gradually bent away from the light source and finally reached a semicircular shape after more than 10 min. A larger rod-like crystal, approximately 10 mm in length, also exhibited a slight bending motion. The cessation of UV irradiation caused the bent crystals to return very slowly to their straight form. In the crystals, the anthracene planes of two neighbouring trans-1 molecules are arranged in a head-to-tail parallel manner, with a short plane-to-plane distance of only 3.72 angstrom. The H-1 nuclear magnetic resonance spectra of trans-1 crystals before and after UV irradiation revealed the intermolecular [4 + 4] photodimerisation of the two anthracene planes, while the trans-to-cis photoisomerisation was not significant. The UV-vis absorption spectra of the trans-1 powder crystals, obtained using a diffuse reflectance spectrophotometer, showed a gradual increase in absorbance between 200 and 500 nm with increasing UV irradiation time, reaching a maximum after 1 h. Thermal back-monomerisation was very slow in the dark, not recovering the initial spectrum even after 25 days. The fluorescence spectra at 570 nm, derived from the anthracene excimer, decreased in intensity with increasing UV irradiation time due to a decrease in the amount of anthracene chromophore via photodimerisation. In situ X-ray measurements revealed that the bending of the crystals was caused by slight elongation of the b axis of the unit cell, corresponding to the long axis of the rod-like crystals. Calculations revealed that the observed crystal elongation could be explained by an optimised head-to-tail [4 + 4] orientation of the anthracene dimer.

Cereblon (CRBN) is encoded by a candidate gene for autosomal recessive nonsyndromic intellectual disability (ID). The nonsense mutation, R419X, causes deletion of 24 amino acids at the C-terminus of CRBN, leading to mild ID. Although abnormal CRBN function may be associated with ID disease onset, its cellular mechanism is still unclear. Here, we examine the role of CRBN in aggresome formation and cytoprotection. In the presence of a proteasome inhibitor, exogenous CRBN formed perinuclear inclusions and co-localized with aggresome markers. Endogenous CRBN also formed perinuclear inclusions under the same condition. Treatment with a microtubule destabilizer or an inhibitor of the E3 ubiquitin ligase activity of CRBN blocked formation of CRBN inclusions. Biochemical analysis showed CRBN containing inclusions were high-molecular weight, ubiquitin-positive. CRBN overexpression in cultured cells suppressed cell death induced by proteasome inhibitor. Furthermore, knockdown of endogenous CRBN in cultured cells increased cell death induced by proteasome inhibitor, compared with control cells. Our results show CRBN is recruited to aggresome and has functional roles in cytoprotection against ubiquitin-proteasome system impaired condition.

Cereblon (CRBN) is encoded by a candidate gene for autosomal recessive nonsyndromic intellectual disability (ID). The nonsense mutation, R419X, causes deletion of 24 amino acids at the C-terminus of CRBN, leading to mild ID. Although abnormal CRBN function may be associated with ID disease onset, its cellular mechanism is still unclear. Here, we examine the role of CRBN in aggresome formation and cytoprotection. In the presence of a proteasome inhibitor, exogenous CRBN formed perinuclear inclusions and co-localized with aggresome markers. Endogenous CRBN also formed perinuclear inclusions under the same condition. Treatment with a microtubule destabilizer or an inhibitor of the E3 ubiquitin ligase activity of CRBN blocked formation of CRBN inclusions. Biochemical analysis showed CRBN containing inclusions were high-molecular weight, ubiquitin-positive. CRBN overexpression in cultured cells suppressed cell death induced by proteasome inhibitor. Furthermore, knockdown of endogenous CRBN in cultured cells increased cell death induced by proteasome inhibitor, compared with control cells. Our results show CRBN is recruited to aggresome and has functional roles in cytoprotection against ubiquitin-proteasome system impaired condition. (C) 2015 Elsevier Inc. All rights reserved.

Cereblon (CRBN) is encoded by a candidate gene for autosomal recessive nonsyndromic intellectual disability (ID). The nonsense mutation, R419X, causes deletion of 24 amino acids at the C-terminus of CRBN, leading to mild ID. Although abnormal CRBN function may be associated with ID disease onset, its cellular mechanism is still unclear. Here, we examine the role of CRBN in aggresome formation and cytoprotection. In the presence of a proteasome inhibitor, exogenous CRBN formed perinuclear inclusions and co-localized with aggresome markers. Endogenous CRBN also formed perinuclear inclusions under the same condition. Treatment with a microtubule destabilizer or an inhibitor of the E3 ubiquitin ligase activity of CRBN blocked formation of CRBN inclusions. Biochemical analysis showed CRBN containing inclusions were high-molecular weight, ubiquitin-positive. CRBN overexpression in cultured cells suppressed cell death induced by proteasome inhibitor. Furthermore, knockdown of endogenous CRBN in cultured cells increased cell death induced by proteasome inhibitor, compared with control cells. Our results show CRBN is recruited to aggresome and has functional roles in cytoprotection against ubiquitin-proteasome system impaired condition. (C) 2015 Elsevier Inc. All rights reserved.

In this study, systems of complicated pathways involved in chiral drug metabolism were investigated. The development of chiral drugs resulted in significant improvement in the remedies available for the treatment of various severe sicknesses. Enantiopure drugs undergo various biological transformations that involve chiral inversion and thus result in the generation of multiple enantiomeric metabolites. Identification of the specific active substances determining a given drug's efficacy among such a mixture of different metabolites remains a challenge. To comprehend this complexity, we constructed a mathematical model representing the complicated metabolic pathways simultaneously involving chiral inversion. Moreover, this model is applied to the metabolism of thalidomide, which has recently been revived as a potentially effective prescription drug for a number of intractable diseases. The numerical simulation results indicate that retained chirality in the metabolites reflects the original chirality of the unmetabolized drug, and a higher level of enantiomeric purity is preserved during spontaneous degradation. In addition, chirality remaining after equilibration is directly related to the rate constant not only for chiral inversion but also for generation and degradation. Furthermore, the retention of chirality is quantitatively predictable using this combination of kinetic parameters. Our simulation results well explain the behavior of thalidomide in the practical biological experimental data. Therefore, this model promises a comprehensive understanding of dynamic metabolic systems involving chiral drugs that express multiple enantiospecific drug efficacies. (C) 2015 Elsevier Ltd. All rights reserved.

In this study, systems of complicated pathways involved in chiral drug metabolism were investigated. The development of chiral drugs resulted in significant improvement in the remedies available for the treatment of various severe sicknesses. Enantiopure drugs undergo various biological transformations that involve chiral inversion and thus result in the generation of multiple enantiomeric metabolites. Identification of the specific active substances determining a given drug's efficacy among such a mixture of different metabolites remains a challenge. To comprehend this complexity, we constructed a mathematical model representing the complicated metabolic pathways simultaneously involving chiral inversion. Moreover, this model is applied to the metabolism of thalidomide, which has recently been revived as a potentially effective prescription drug for a number of intractable diseases. The numerical simulation results indicate that retained chirality in the metabolites reflects the original chirality of the unmetabolized drug, and a higher level of enantiomeric purity is preserved during spontaneous degradation. In addition, chirality remaining after equilibration is directly related to the rate constant not only for chiral inversion but also for generation and degradation. Furthermore, the retention of chirality is quantitatively predictable using this combination of kinetic parameters. Our simulation results well explain the behavior of thalidomide in the practical biological experimental data. Therefore, this model promises a comprehensive understanding of dynamic metabolic systems involving chiral drugs that express multiple enantiospecific drug efficacies. (C) 2015 Elsevier Ltd. All rights reserved.

:In this study, systems of complicated pathways involved in chiral drug metabolism were investigated. The development of chiral drugs resulted in significant improvement in the remedies available for the treatment of various severe sicknesses. Enantiopure drugs undergo various biological transformations that involve chiral inversion and thus result in the generation of multiple enantiomeric metabolites. Identification of the specific active substances determining a given drug׳s efficacy among such a mixture of different metabolites remains a challenge. To comprehend this complexity, we constructed a mathematical model representing the complicated metabolic pathways simultaneously involving chiral inversion. Moreover, this model is applied to the metabolism of thalidomide, which has recently been revived as a potentially effective prescription drug for a number of intractable diseases. The numerical simulation results indicate that retained chirality in the metabolites reflects the original chirality of the unmetabolized drug, and a higher level of enantiomeric purity is preserved during spontaneous degradation. In addition, chirality remaining after equilibration is directly related to the rate constant not only for chiral inversion but also for generation and degradation. Furthermore, the retention of chirality is quantitatively predictable using this combination of kinetic parameters. Our simulation results well explain the behavior of thalidomide in the practical biological experimental data. Therefore, this model promises a comprehensive understanding of dynamic metabolic systems involving chiral drugs that express multiple enantiospecific drug efficacies.

In the title compound, C&lt
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H&lt
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N&lt
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O&lt
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, the phthalimide ring system is essentially planar, with a maximum deviation of 0.0479 (14) Å. In the crystal, each molecule is linked via six neighbouring molecules into a three-dimensional network through N - H⋯O and O - H⋯O hydrogen bonds, which form an R &lt
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(8) ring motif.

We report on the self-disproportionation of enantiomers (SDE) of non-racemic thalidomide (1) and 3'-fluorothalidomide (2) under the conditions of gravity-driven achiral silica-gel chromatography. The presence of a fluorine atom on the chiral center dramatically alters the structure and polarity of 1 and 2, resulting in the opposite SDE profile on silica-gel.

Amyloid protein (A beta) plays a central role in the pathogenesis of Alzheimer's disease (AD). Point mutations within the A sequence associated with familial AD (FAD) are clustered around the central hydrophobic core of A. Several types of mutations within the A sequence have been identified, and the Arctic' mutation (E22G) has a purely cognitive phenotype typical of AD. Previous studies have shown that the primary result of the Arctic' mutation is increased formation of A protofibrils. However, the molecular mechanism underlying this effect remains unknown. A42 binds to a neuronal nicotinic acetylcholine receptor subunit, neuronal acetylcholine receptor subunit alpha-7 (CHRNA7), with high affinity and, thus, may be involved in the pathogenesis of AD. Therefore, to clarify the molecular mechanism of Arctic mutation-mediated FAD, we focused on CHRNA7 as a target molecule of Arctic A. We performed an in vitro binding assay using purified CHRNA7 and synthetic Arctic A40, and demonstrated that Arctic A40 specifically bound to CHRNA7. The aggregation of Arctic A40 was enhanced with the addition of CHRNA7. Furthermore, the function of CHRNA7 was detected by measuring Ca2+ flux and phospho-p44/42 MAPK (ERK1/2) activation. Our results indicated that Arctic A40 aggregation was enhanced by the addition of CHRNA7, which destabilized the function of CHRNA7 via inhibition of Ca2+ responses and activation of ERK1/2. These findings indicate that Arctic A mutation may be involved in the mechanism underlying FAD. This mechanism may involve binding and aggregation, leading to the inhibition of CHRNA7 functions.

To improve our ability to identify single crystals causing arthritis, we have developed a practical measurement system of polarized light microscopy called advanced compensated polarized light microscopy (A-CPLM). The A-CPLM system is constructed by employing a conventional phase retardation plate, an optical fibre and a charge-coupled device spectrometer in a polarized light microscope. We applied the A-CPLM system to measure linear birefringence (LB) in the visible region, which is an optical anisotropic property, for tiny single crystals causing arthritis, i.e. monosodium urate monohydrate (MSUM) and calcium pyrophosphate dihydrate (CPPD). The A-CPLM system performance was evaluated by comparing the obtained experimental data using the A-CPLM system with (i) literature data for a standard sample, MgF2, and (ii) experimental data obtained using an established optical method, high-accuracy universal polarimeter, for the MSUM. The A-CPLM system was found to be applicable for measuring the LB spectra of the single crystals of MSUM and CPPD, which cause arthritis, in the visible regions. We quantitatively reveal the large difference in LB between MSUM and CPPD crystals. These results demonstrate the usefulness of the A-CPLM system for distinguishing the crystals causing arthritis.

:We propose, as an alternative to conventional spectroscopic assays, a simple method for discriminating fibrous amyloid proteins by using a label-free semiconductor-based biosensor. The highly sensitive assay is expected to be useful for accelerating amyloid related research.

A novel method for fabricating anisotropic collagen membranes, which regulate the preferred orientation, is developed. The high-accuracy universal polarimeter (HAUP) method is used for simultaneous and quantitative evaluations of the optical anisotropy and optical activity. The evaluation of these optical quantities, enabled by the HAUP method, is beneficial to the field of tissue engineering.

:Amyloid β protein (Aβ) plays a central role in the pathogenesis of Alzheimer's disease (AD). Point mutations within the Aβ sequence associated with familial AD (FAD) are clustered around the central hydrophobic core of Aβ. Several types of mutations within the Aβ sequence have been identified, and the 'Arctic' mutation (E22G) has a purely cognitive phenotype typical of AD. Previous studies have shown that the primary result of the 'Arctic' mutation is increased formation of Aβ protofibrils. However, the molecular mechanism underlying this effect remains unknown. Aβ42 binds to a neuronal nicotinic acetylcholine receptor subunit, neuronal acetylcholine receptor subunit alpha-7 (CHRNA7), with high affinity and, thus, may be involved in the pathogenesis of AD. Therefore, to clarify the molecular mechanism of Arctic mutation-mediated FAD, we focused on CHRNA7 as a target molecule of Arctic Aβ. We performed an in vitro binding assay using purified CHRNA7 and synthetic Arctic Aβ40, and demonstrated that Arctic Aβ40 specifically bound to CHRNA7. The aggregation of Arctic Aβ40 was enhanced with the addition of CHRNA7. Furthermore, the function of CHRNA7 was detected by measuring Ca(2+) flux and phospho-p44/42 MAPK (ERK1/2) activation. Our results indicated that Arctic Aβ40 aggregation was enhanced by the addition of CHRNA7, which destabilized the function of CHRNA7 via inhibition of Ca(2+) responses and activation of ERK1/2. These findings indicate that Arctic Aβ mutation may be involved in the mechanism underlying FAD. This mechanism may involve binding and aggregation, leading to the inhibition of CHRNA7 functions.

We propose, as an alternative to conventional spectroscopic assays, a simple method for discriminating fibrous amyloid proteins by using a label-free semiconductor-based biosensor. The highly sensitive assay is expected to be useful for accelerating amyloid related research.

A novel method for fabricating anisotropic collagen membranes, which regulate the preferred orientation, is developed. The high-accuracy universal polarimeter (HAUP) method is used for simultaneous and quantitative evaluations of the optical anisotropy and optical activity. The evaluation of these optical quantities, enabled by the HAUP method, is beneficial to the field of tissue engineering.

A metastable liquid crystal (LC) was found to serve as a time responsive reaction medium, in which the enantioselectivity of a photoreaction was perfectly switched through isothermal annealing of the reaction system. When the LC salt of an enantiopure amine with a photoreactive acid was irradiated with UV/vis light, in situ, photodimerization of the acid moiety proceeded smoothly to afford the (+)-isomer of the photodimer with high enantioselectivity (+86% ee). In contrast, photoirradiation of an aged sample, isothermally annealed for 20 h, gave predominantly the (-)-isomer (-94% ee). Systematic studies revealed that the reversal in selectivity originated from metastability. of the LC system, which gradually transformed into a crystalline phase during annealing. This finding demonstrates the potential use of metastable aggregates as dynamic time-responsive media, reminiscent of biological systems.

A metastable liquid crystal (LC) was found to serve as a time responsive reaction medium, in which the enantioselectivity of a photoreaction was perfectly switched through isothermal annealing of the reaction system. When the LC salt of an enantiopure amine with a photoreactive acid was irradiated with UV/vis light, in situ, photodimerization of the acid moiety proceeded smoothly to afford the (+)-isomer of the photodimer with high enantioselectivity (+86% ee). In contrast, photoirradiation of an aged sample, isothermally annealed for 20 h, gave predominantly the (-)-isomer (-94% ee). Systematic studies revealed that the reversal in selectivity originated from metastability. of the LC system, which gradually transformed into a crystalline phase during annealing. This finding demonstrates the potential use of metastable aggregates as dynamic time-responsive media, reminiscent of biological systems.

The proton motive force (PMF) is bio-energetically important for various cellular reactions to occur. We developed PMF-photogenerating mitochondria in cultured mammalian cells. An archaebacterial rhodopsin, delta-rhodopsin, which is a light-driven proton pump derived from Haloterrigena turkmenica, was expressed in the mitochondria of CHO-K1 cells. The constructed stable CHO-K1 cell lines showed suppression of cell death induced by rotenone, a pesticide that inhibits mitochondrial complex I activity involved in PMF generation through the electron transport chain. Delta-rhodopsin was also introduced into the mitochondria of human neuroblastoma SH-SY5Y cells. The constructed stable SH-SY5Y cell lines showed suppression of dopaminergic neuronal cell death induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), an inducer of Parkinson's disease models, which acts through inhibition of complex I activity. These results suggest that the light-activated proton pump functioned as a PMF generator in the mitochondria of mammalian cells, and suppressed cell death induced by inhibition of respiratory PMF generation.

Most polymers solidify below a glass transition temperature (;), which is important for the fabrication of polymeric materials. The glass transition dynamics (GTD) of polymers alters their physical properties and therefore the range of applications suitable for the particular materials. In this regard, most GTD studies were oriented to the thermodynamics of amorphous polymer systems, while little studies were known for semicrystalline polymers. Here, we focus on the glassy and crystalline properties of semicrystalline polymers such as poly(L-lactic acid) (PLLA) and envisage to control the nanostructure of free-standing PLLA ultrathin films (referred as "PLLA nanosheets"), via thermodynamic rearrangement of polymer chains entangled in a quasi-two-dimensional interface during the GTD process. The annealing process on the PLLA nanosheets (&lt;100 nm thick) resulted in the formation of semicrystalline domains and microscopic apertures with polymer chains (similar to 100 nm in size). Such nanostructure surprisingly induced selective molecular permeability, which was controlled as a function of film thickness and inherent crystallinity. The present methodology demonstrates the direct conversion of thermodynamic properties of semicrystalline polymers into the functional nanostructured polymeric materials.

The advanced high-accuracy universal polarimeter (HAUP) method was applied to observe anisotropic and chiroptical properties of an intercalated azobenzene derivative compound into K4Nb6O17 crystals. Prior to the HAUP measurement of the intercalated compound, we extended the HAUP method employing a conventional light source system composed of Xe or D-2 lamps and a monochromator instead of a laser system. The performance of the advanced HAUP system was evaluated and we determined the parasitic ellipticities of the cross polarizers, which are essential for obtaining accurate values. The optical system was applicable to simultaneously measure the linear dichroism (LD), circular dichroism (CD), linear birefringence (LB) and circular birefringence (CB) spectra of an intercalated compound in the ultraviolet and visible regions. We found the Kramers-Kronig relation between CB and CD as well as in the case of LB and LD. Changes in LB and LD signals as obtained from HAUP measurements originated from the molecular orientation of guest molecules by the intercalation. Moreover, CB and CD signals indicated the appearance of induced chirality in the intercalated azobenzene derivative compound. These results demonstrated the usefulness of the HAUP system for evaluating the molecular conformation of chiral anisotropic specimens.

Crystal specimens of the gamma-polymorph of achiral glycine which crystallize in space groups P3(1) and P3(2) as determined by the anomalous X-ray scattering method are shown to be laevorotatory and dextrorotatory, respectively, as determined by optical rotation of the crystals.

The lamellar architecture found in many natural fibrous tissues has a significant bearing on their specific functions. However, current engineered tissues have simultaneously no realistic structures and no adequate functions. This study demonstrates a two-step process for obtaining structurally mimicking laminates in natural fibrous tissues with good optical and mechanical characters from purified-clinically-safe collagen molecules. Stacked lamella structures can be created by repeating flow casting, with the controlling parallel/orthogonal directionalities of each thin single-layer (2-5 mu m in thickness). The transparency of laminates is successfully improved by a unique multi-cyclic vitrification with chemical cross-linking. The directionalities of optical and mechanical functions in laminates are strongly related with the preferential collagen alignments in the laminates. The tensile strength of laminates is extremely higher than any other engineered materials as well as native cornea, which exhibit an orthogonal laminated collagen structure and a good optical transmission. (C) 2010 Elsevier Ltd. All rights reserved.

Although polyethylene oxide (PEO) offers several advantages as a sieving polymer in SDS capillary polymer electrophoresis (SDS-CPE), solution properties of PEO cause deterioration in the electrophoresis because PEO in solution aggregates itself, degrades into smaller pieces, and forms polymer-micelle complexes with SDS. We examined protein separation on SDS-CPE with PEO as a sieving matrix in four individual buffer solutions: Tris-CHES, Tris-Gly, Tris-Tricine, and Tris-HCl buffers. The solution properties of PEO as a sieving matrix in those buffers were examined by dynamic light scattering (DLS) and by surface tension. Preferential SDS adsorption onto PEO disturbed protein-SDS complexation and impaired the protein separation efficiency. Substantial adsorption of SDS to PEO was particularly observed in Tris-Gly buffer. The Tris-CHES buffer prevented SDS from adsorbing onto the PEO. Only Tris-CHES buffer achieved separation of six proteins. This study demonstrated efficient protein separation on SDS-CPE with PEO.

SmCo5 alloy is a promising candidate for ultra-high-density perpendicular magnetic recording (PMR) media because of its high uniaxial magnetocrystalline anisotropy K-u of more than 1.1 x 10(8) erg/cm(3). Previously, we successfully achieved high K-u in a sputter-deposited SmCo5 thin film by introducing a Cu/Ti dual underlayer. However, in order to apply the SmCo5 films to practical PMR media, it is necessary to decrease medium noise. A granulated magnetic film comprising of small and magnetically decoupled grains is effective in reducing the medium noise. In this paper, we have proposed a new granular film that is fabricated by partial thermodiffusion of Cu between the Sm-Co continuous layer and the Cu underlayer, which is granulated using compositional segregation caused by the addition of Ta2O5. We have analyzed the magnetic properties, magnetic domain size, and magnetization reversal process of the proposed SmCo5 film. The magnetic domain size decreased and the magnetization reversal process changed from the magnetic-wall-motion mode to a coherent rotation mode to some extent on isolation of magnetic grains. The read/write characteristics of granulated SmCo5 double-layered media were also evaluated. The medium noise decreased and the signal-to-noise ratio increased for the granulated double-layered (PMR) medium. (C) 2010 Elsevier B.V. All rights reserved.

A Sm-Co-CrTa granular layer between a Sm-Co continuous layer and a Cu underlayer was prepared in order to improve magnetic properties and magnetic reversal process of Sm-Co perpendicular film. A phase of CrTa alloy in Sm-Co-CrTa layer has a role in control of Cu partial interlayer diffusion between the Sm-Co continuous layer and the Cu underlayer. The Cu diffusion provides the partial crystallization of SmCo5 in the continuous layer. Although the perpendicular coercivity of films decreased slightly by introducing the CrTa alloy into Sm-Co layer, the magnetic intergranular exchange interaction in the films was drastically improved. Size of average magnetic cluster became smaller and magnetization reversal process was changed from a wall-motion to a coherent rotation for increasing the thickness ratio of Sm-Co-CrTa/Sm-Co layers. We confirmed that an addition of Sm-Co-CrTa layer is effective to reduce the intergranular exchange interaction in Sm-Co perpendicular films without deterioration of perpendicular magnetic anisotropy.

Stem cells nanotechnology has emerged as a new exciting area, and holds great potential for research and development of stem cells as novel therapeutic platforms for genetic, traumatic, and degenerative medicine. Vital to the success of this technology are approaches that reproducibly facilitate in vivo cell tracking, expansion, differentiation, and transplantation. Herein we reported the effects of CdSe/ZnS quantum dots covered multi-walled carbon nanotubes (FMNTs) on mice embryonic stem cell line CCE cells. The FMNTs were prepared by plasma surface treatment and characterized by high resolution transmission electron microscopy (HR-TEM), and incubated with murine ES CCE cells for 1 to 28 day.These ES cells were observed by confocal laser scanning microscopy, and were analyzed by real time reverse transcription-polymerase chain reaction (RTPCR), flow cytometry (FCM) and MTT method. Results showed that prepared FMNTs exhibited green fluorescent signal, could enter into ES cells in time-dependent means, more than 20 μg ml-1 FMNTs induced ES cells become smaller and smaller as the incubation time increased, and inhibited cell growth in dose-and time-dependent means, induced apoptosis of ES cells
conversely, 5 μg ml-1 FMNTs could markedly stimulate the expression of Sox1 and Hsp27, and inhibit expression of OCT4 in ES cells, FCM analysis showed that differentiation marker Flk-1 exhibited higher expression compared with control ES cells. In conclusion, high dose of FMNTs can inhibit proliferation of ES cells, low dose of FMNTs can improve the differentiation of ES cells, FMNTs can have potential applications in in vivo tracking, imaging and regulation of the proliferation and differentiation of ES cells. © 2010 D. Cui, et al.

Carbon nanotubes'bio-effects have become a hotspot. In recent years, my group and collaborators try to use single walled carbon nanotubes(SWCNTs) as drug delivery system to regulate proliferation and differentiation of mouse stem cells. We observed that low dose of SWCNTs stimulate stem cells'proliferation and differentiation, higher dose of SWCNTs improve stem cells' apoptosis. Y-27632, a selective inhibitor of p160 Rho-associated coiled-coil kinase, can conjugate with SWCNTs and form the nanocomposites, which markedly inhibit the apoptosis of mouse stem cells, improve the proliferation and differentiation of stem cells. The potential mechanism of effects of Y-27632-SWCNT composites on stem cells is also dicussed. Our primary results suggest that special enzyme modified SWCNTs can be used to regulate proliferation and differentiation of stem cells, which has potential application in stem cells-based therapy. ©The Electrochemical Society.

A highly selective, ultrasensitive, fluorescence detection method for DNA and antigen based on self-assembly of multiwalled carbon nanotubes (CNTs) and CdSe quantum dots (QDs) via oligonucleotide hybridization is reported. Mercaptoalkyloligonucleotide molecules bind to the quantum dots, while amineoalkyloligonucleotides bind to CNTs with -COCl surface groups. QDs and CNTs further assemble into nanohybrids through DNA hybridization in the presence of target complementary oligonucleotides. The method is achieved with good repeatability with the detection limit of 0.2 pM DNA molecules and 0.01 nM antigen molecules. This novel detection system can also be used for multicomponent detection and antigen-antibody immunoreaction. The novel system has great potential in applications such as ultrasensitive pathogen DNA or antigen or antibody detection, molecular imaging, and photoelectrical biosensors.

An SmCo(5) alloy is a promising candidate for ultra-high density magnetic recording media because of its strong uniaxial magnetocrystalline anisotropy, whose constant, K(u), is more than 1.1 x 10(8) erg/cm(3). Recently, we successfully obtained high perpendicular magnetic anisotropy for a sputter-deposited SmCo(5) thin film by introducing a Cu/Ti dual underlayer. However, it is necessary to improve magnetic properties and read/write (R/W) characteristics for applying SmCo(5) thin films to perpendicular magnetic recording media. In this study, we focused on reduction of magnetic domain size and change of a magnetization reversal process of SmCo(5) perpendicular magnetic thin. films by introducing carbon (C) atoms into the constituent Cu underlayer. The magnetic domain size became small and the ratio of coercivity (H(c)) against magnetic anisotropy (H(k)) which is an index of the magnetization reversal process was increased by adding C atoms. We also evaluated the R/W characteristics of SmCo(5) double-layered media including C atoms. The medium noise was decreased and signal-to-noise ratio increased by introducing the C. The addition of C into the Cu underlayer is effective for changing the magnetization reversal process, reducing medium noise and increasing SNR. (C) 2008 Published by Elsevier B. V.

Magnetic circular dichroism (MCD) and X-ray absorption spectra (XAS) at the Co L(2,3)-edge of [Co/Pd](20) and [CoB/Pd](20) multilayered films, which were fabricated at 260 degrees C with different magnetic layer thicknesses (delta), have been measured. The lineshapes of XAS-MCD show that the electronic state of Co 3d of the films hardly changes even when sputtered at higher temperatures. The expectation values of orbital and spin angular momentum (&lt; L(z)&gt; and &lt; S(z)&gt;) are estimated using the sum rule, and it is found that &lt; L(z)&gt;/&lt; S(z)&gt; in delta&lt;0.5 nm is larger than that in delta&gt;0.5 nm. (C) 2008 Elsevier B. V. All rights reserved.

An extremely enhanced enantioselectivity was achieved for the detection of enantiomers of alanine (Ala), leucine (Leu), and 3,4-dihydroxyphenylalanine (DOPA) based on the voltammograms for the deposition of Cu from Cu complexes of the amino acids at an Au electrode modified with a self-assembled monolayer (SAM) Of L-homocysteine (Hcy). The enantioselective current density peak for the Cu deposition was found to change with increasing number of potential cycles after the addition of Cu(II), and the highest enantioselectivity was observed immediately after the addition of Cu(II). Besides, enantio selectivity was not observed with proline, whose five-membered ring contains the nitrogen atom of a secondary amino group, while some amino acids with a primary amine group such as Ala, Leu, and DOPA exhibited enantioselectivity. These results suggest that the chiral ligand exchange reaction at the L-Hcy SAM-modified Au electrode, namely, the enantioselective formation of diastereomeric complexes of Cu(II) with target enantiomers and L-Hcy self-assembled on the Au electrode, plays an important role in the chiral discrimination based on the Cu deposition. (c) 2006 Elsevier B.V. All rights reserved.

Sputter-deposited SmCos thin films exhibiting high perpendicular magnetic anisotropy were studied for materializing ultra high density magnetic recording. This study put emphasis on the fabrication of SmCos double-layered perpendicular magnetic recording media. A double-layered medium with a Ru buffer layer introduced between a Cu/Ti intermediate layer and a Co-Zr-Nb soft magnetic underlayer exhibited high perpendicular magnetic anisotropy, whereas that without the Ru buffer layer did not. Auger electron spectroscopy revealed that the Ru buffer layer inhibited unfavorable interdiffusion between the Cu/Ti intermediate layer and the Co-Zr-Nb soft magnetic underlayer. In addition, the readwrite characteristics of the SmCos double-layered perpendicular magnetic recording media were evaluated for the first time. copyright The Electrochemical Society.

The soft x-ray absorption and magnetic circular dichroism spectra at the Co L-2,L-3-edges of [Co/Pd](20) and [CoB/Pd](20) multilayered films, which were sputter- deposited in Ar gas containing N-2 at room temperature, were measured to investigate the electronic and spin states of the films. The macroscopic magnetic properties, such as coercivity and saturation magnetization, and microstructural properties, such as grain size and preferred orientation, were markedly changed for the [Co/Pd](20) film by the B doping and N-2 addition. The B doping and/or the addition of N-2 gas caused appreciable changes not only in macroscopic magnetic properties but also in microscopic properties, such as the spin angular momentum and orbital angular momentum, throughout the multilayered film. On the other hand, a new spectral feature at the high energy side of the Co L-3-edge peak in x-ray absorption spectra was found in only the films with N-2 added. Thus, the microscopic properties, such as electronic and spin states, of the Co 3d electronic state for the [Co/Pd](20) and [CoB/Pd](20) films were changed by only the sputtering process with additive N-2 gas.

Effects of the Cu underlayer thickness and the addition Of Cu to a Sm-Co layer on magnetic properties and microstructure Of SmCo5 thin films exhibiting perpendicular magnetic anisotropy were studied. The origin of the perpendicular magnetic anisotropy was discussed from these experimental results. A thick Cu underlayer of more than 100 nm brought about high perpendicular magnetic anisotropy leading to the squareness ratio equal to unity. The Cu addition enhanced the perpendicular magnetic anisotropy and reduced the Cu underlayer thickness required to obtain the squareness ratio of unity. X-ray diffractometry showed that the crystalline orientation of the Sm-Co layer did not correlate with that of the Cu underlayer. Auger electron spectroscopy revealed that Cu atoms were diffused up to the Sm-Co layer from the Cu underlayer. From the results, Cu atoms existing in the Sm-Co layer were suggested to be strongly related with an appearance of the perpendicular magnetic anisotropy by introducing the Cu underlayer. (c) 2005 Elsevier B.V. All rights reserved.

The effect of the surface morphology of gold-deposited quartz substrate on the enantioselective crystallization of leucine was investigated by using quartz crystal microbalance (QCM) and X-ray diffraction methods. The gold substrate was modified with a self-assembled monolayer with covalently attached D-leucine molecules. For a rough surface with root-mean-square (RMS) roughness of 17 nm, the QCM measurement showed a continuous decrease in frequency, while for a smooth surface with RMS roughness of 2 nm, essentially no change in frequency was observed. Nevertheless, leucine crystals with high crystallinity were clearly formed on the smooth surface.

X-ray absorption and magnetic circular dichroism spectra (XAS-MCD) of the Dy M-4,M-5-edges of DyxCo100-x (x=15-33) thin films are measured. The advantage of element and orbital selectivity in the XAS-MCD measurements enables us to directly observe the magnetic moments of specified elements. The MCD intensity at the Dy M-5-edge is maximum when the incident X-ray is normal to the surface and the incident angle dependence of the MCD intensity shows a sine curve. That gives us information about the angular distribution of the Dy magnetic moments with respect to the total magnetization direction and the opening angle of the cone. Applying the sum rule, the expectation value of orbital magnetic moment was estimated. The half opening angle of the random distribution of the moments were estimated and it was found that the angle has its minimum value around x=20. (c) 2005 Elsevier B.V. All rights reserved.

The effects of the thicknesses of a Cu/Ti underlayer and a Sm-Co layer on the magnetic properties and domain structure of SmCo₅ perpendicular magnetization films prepared by using an ultra-high-vacuum sputtering system were investigated. By adjusting the thicknesses of both the Cu/Ti underlayer and the Sm-Co layer, the coercivity was controlled to be a moderate value, allowing the films to be used in magnetic recording media while maintaining a squareness ratio of unity. As the Sm-Co layer thickness was reduced, the magnetic cluster size decreased and the magnetization reversal process varied from wall motion mode to a rotation mode. It is suggested that the Cu-rich region in the initial growth stage of the Sm-Co layer functions as the pinning site of the magnetic domain wall and plays an important role in controlling the magnetic domain structure.

An investigation was carried out on the effects of the addition of Cu and the thickness of the SmCo5-based thin film with perpendicular magnetic anisotropy upon its magnetic properties, with the aim of reducing the Cu/Ti underlayer thickness. As a result, the Cu/Ti underlayer thickness necessary to obtain the squareness ratio of unity was successfully reduced from 125 to 50 nm. Moreover, for the SmCo5 double-layered perpendicular magnetic recording media with a CoZrNb soft magnetic underlayer, the Cu/Ti underlayer thickness was further reduced to 35 nm. However, the magnetic cluster size and the values of coercivity and saturation field of the SmCo5 media were found to be too large. Thus, we recognized the need for adjusting the cluster size and the magnetic properties to appropriate values, and also the need for investigating the possibility of using this material as patterned media or thermally assisted recording media.

Effects of the Pd seeds formed by an electrochemical process on the microstructures of Co/Pd multilayered perpendicular recording media were investigated. By immersing a CoZrNb soft magnetic underlayer (SUL) into PdCl2 aqueous solution, island-like Pd clusters were deposited on the SUL, resulting from the electrochemical substitution reaction. Transmission electron microscopic observations revealed that the columnar Co/Pd multilayered grains with clear boundaries grew on the SUL with the Pd clusters. The clear grain boundaries, where the densities of Co and Pd elements were low, were thought to cause the magnetic exchange decoupling between the Co/Pd grains, leading to an increase of perpendicular coercivity and a decrease of magnetic cluster size of Co/Pd multilayered film. Consequently, lower medium noise was obtained for the Co/Pd multilayered medium with the Pd clusters than for that with a sputter-deposited Pd seedlayer. From these investigations, it was clarified that the SUL surface with Pd clusters provided the effective nucleation sites for a well-defined Co/Pd multilayered grain growth. (C) 2004 Elsevier B.V. All rights reserved.

SmCo5 thin films with Cu seedlayer exhibiting perpendicular magnetic anisotropy were studied. The perpendicular magnetic anisotropy was enhanced using the Sm-Co layer formed by laminating Co and Sm sub-layers alternately. The Co/Sm laminate structure promoted the crystallization Of SmCo5 and the preferred orientation of its c-axis. The perpendicular magnetic anisotropy was further improved by suppressing the surface roughness of the Cu seedlayer. The SmCo5 thin film prepared in this study possesses an adequate corrosion resistance when judged by an electrochemical analysis. (C) 2004 Elsevier B.V. All rights reserved.

A novel fabrication process of a soft magnetic underlayer (SUL) for a double-layered perpendicular magnetic recording medium was presented. The CoNiFeB SUL was deposited on a silicon disk substrate using an electroless deposition. The Ni seed layer for the electroless deposition was prepared by an electrochemical process. The surface of the deposited SUL was subjected to a chemical mechanical polishing to be flattened, and R-a value of the SUL was less than 0.4 nm. A magnetic domain structure greatly depended on the electroless deposition condition. Particularly, the control of an agitation speed during electroless deposition is much effective for the suppression of distinct domain walls appearing in CoNiFeB underlayers. (C) 2004 Published by Elsevier B.V.

Effects of N-2 additive gas and/or substrate heating during the sputtering of [CoB/Pd](20) multilayered films on the magnetic properties and microstructure were investigated. The [CoB/Pd](20) film fabricated at 20degreesC by adding N-2 gas during sputtering possessed the finest grain size and the smallest magnetic cluster size among media fabricated in this study although the film sputter-deposited at 260 degreesC by adding N-2 gas exhibited the weakest intergranular exchange coupling. It was revealed that the double-layered perpendicular magnetic recording medium that consisted of the [CoB/Pd](20) film fabricated at 20degreesC by adding N-2 gas exhibited the highest signal-to-noise ratio in the read write characteristics. (C) 2004 Elsevier B.V. All rights reserved.

Thin films of SmCo5 with extraordinarily high perpendicular magnetic anisotropy were prepared by introducing a Cu/Ti dual underlayer and controlling the substrate temperature during the sputter deposition. Under optimized conditions, the magnetic anisotropy constant reached 4.0x10(7) erg/cm(3), and the coercivity and the remanence ratio in the direction perpendicular to the film surface were 12.0 kOe and unity, respectively. The high perpendicular magnetic anisotropy is attributed to the high degree of preferred orientation of the c axis; the full width at half maximum in the rocking curve of SmCo5(002) reflection was 3.1degrees. (C) 2004 American Institute of Physics.

Pd cluster seeds for a double-layered perpendicular magnetic recording medium composed of a Co/Pd multilayered film and a CoZrNb soft magnetic underlayer (SUL) were fabricated with an electrochemical treatment. By immersing the SUL into an aqueous PdCl2 solution, the substitution of Pd for Co at the surface of the SUL took place, which was caused by the difference in electrochemical redox potential between Pd and Co. Uniformly distributed Pd clusters with 8 nm in diameter were successfully formed with the treatment for the optimized duration. Use of the Pd clusters as the seeds for deposition of the Co/Pd multilayered film increased the perpendicular coercivity and reduced the size of magnetic cluster of the film. These results suggested that the Pd cluster seeds led to the formation of magnetically isolated Co/Pd multilayered grains, improving the magnetic properties of Co/Pd multilayered film.

The electronic and spin states of [Co/Pd] multilayered perpendicular magnetization films with various seedlayers have been investigated by means of soft x-ray absorption and magnetic circular dichroism spectroscopy at the Co L-2,L-3-edges. The expectation values of the orbital angular momentum &lt;L-z&gt; and the spin angular momentum &lt;S-z&gt; of Co atom in the [Co/Pd] multilayered film were estimated using the sum rule. It was found that the seedlayer changes macroscopic magnetic properties of the [Co/Pd] multilayered film without affecting the electronic and spin states of the upper layers of Co. (C) 2004 American Institute of Physics.

A 10 nm Pd/Si dual thin film was developed as a seed layer for a Co/Pd multilayer in double-layered perpendicular magnetic recording media. The Pd/Si seed layer, sputter deposited under Ar sputtering gas containing N-2 and postannealed at 400 degreesC, markedly reduced intergranular exchange coupling of the Co/Pd multilayered film, resulting in a decrease in both the slope parameter, defined as 4pi(dM/dH)(H=Hc), and the magnetic cluster size. Consequently, medium noise was essentially reduced, thereby improving the signal-to-noise ratio of the Co/Pd recording media on a CoZrNb soft magnetic underlayer. The addition of N-2 gas effectively decreased the grain size of Pd in the seed layer. A Pd/Si seed layer prepared with both processes exhibited a granular structure of fine Pd-rich grains surrounded by a Si-rich amorphous region, which provided nucleation sites for the growth of well-separated Co/Pd multilayered grains. (C) 2004 American Institute of Physics.

Cu下地層を有するSmCo_5垂直磁化膜について検討した.Sm-Co層の形成時にCo/Sm積層構造を利用して膜厚方向の組成変調を与えることにより,その垂直磁気異方性が強調された.このCo/Sm積層構造は,SmCo_5相の結晶化を促進し,また,その磁化容易軸であるc軸の垂直配向性を向上させるために有効であった.また,Cu下地層の表面ラフネスを低減させることにより,垂直磁気異方性は更に増大した.電気化学測定法により評価したところ,本研究で作製したSmCo_5薄膜の耐食性は,過去に報告されたCo-Cr/Ti垂直磁化膜のそれと同程度であることがわかった.

Microstructure and magnetic properties of sputter deposited Co/Pd multilayered perpendicular magnetization films with amorphous C or Si seedlayer were investigated. The angstrom scale surface roughness of the seedlayer causes fine crystal grains to form in the Co/Pd multilayer and to decrease the extent of intergranular exchange coupling, while it obstructs the formation of a regular interface between Co and Pd layers. The Si seedlayer, which exhibits a surface roughness lower than the C seedlayer, yields Co/Pd multilayered films with the lowest intergranular exchange coupling and the highest coercivity. The improvement in magnetic properties of the Co/Pd film with Si seedlayer is attributable mainly to the formation of Pd2Si at the interface between the Co/Pd layer and the Si seedlayer. The Pd2Si provides suitable nucleation sites for the grain growth of Co/Pd multilayered film that can be utilized as a perpendicular magnetic recording medium. (C) 2002 American Institute of Physics.

Effects of the introduction of a Pd/Si dual seedlayer on the microcrystalline structure and magnetic properties of [Co/Pd](n) multilayered perpendicular magnetic recording media were investigated. The Pd/Si dual seedlayer was composed of a Pd upper seedlayer and a Si under seedlayer. The Pd upper seedlayer with a thickness of up to 10 nm markedly increased the coercivity of [Co/Pd](n) multilayered media in the direction perpendicular to the film surface. The highest coercivity of 7.8kOe was obtained for the [Co/Pd](10) medium with a Pd (10nm)/Si (100nm) dual seedlayer. The Pd upper seedlayer not only facilitated the formation of regular interfaces between the Co and Pd layers, but also reduced the thickness of the deteriorated initial layer in the [Co/Pd](n) multilayer, resulting in enhancement of the magnetic anisotropy field. The [Co/Pd](n) multilayered medium with the Pd/Si dual seedlayer exhibited weak intergranular exchange coupling between [Co/Pd](n) grains, which led to excellent read-write characteristics. (C) 2002 Elsevier Science B.V. All rights reserved.

The relationship between crystallographic grain orientation and the three kinds of surface energy components; dispersion, polar, and hydrogen bonding components, in Co73Cr18Pt6Ta3 perpendicular magnetic recording media with an amorphous C or a Ti90Cr10 underlayer was discussed. Each surface energy component of the thin film was calculated from an extended Fowkes theory by measuring the contact angle of a test liquid on the thin film. The experimental results revealed that the polar component of surface energy of the Co73Cr18Pt6Ta3 magnetization film with the C underlayer affected greatly the Co [001] preferred orientation of the Co73Cr18Pt6Ta3 magnetization film, while the surface energy of the Co73Cr18Pt6Ta3 magnetic layer with the Ti90Cr10 underlayer had little influence on the distribution of it. (C) 2001 Elsevier Science B.V. All rights reserved.

Signal and noise characteristics of Co/Pd multilayer perpendicular magnetic recording media are discussed based upon MFM analysis. The noise of the Co/Pd multilayer media is originated mainly from irregularities in the magnetic transition regions, and can be drastically suppressed by increasing the thickness of the carbon underlayer although a large number of reversed magnetic domains between the magnetic transitions still exist. The fine magnetic clusters formed in the medium with a thick carbon underlayer result in clear magnetic transition boundaries of recorded bits in the high recording density region. By examining the profile of the M-H loops. the decrement in the x value, which is defined as the slope of M-H loop at the value of coercivity, improves the signal to noise (S/N) ratio for the Co/Pd multilayer media. (C) 2001 Elsevier Science B.V. All rights reserved.

The effect of amorphous carbon underlayer thickness on the microstructure of the CO/Pd multilayer perpendicular magnetic recording media was investigated. From the magnetic force microscopy observation in the AC-demagnetized state of the Co/Pd multilayer media, the magnetic cluster size was observed to effectively decrease with an increase in carbon underlayer thickness, where the higher coercivity and the higher SIN ratio of the Co/Pd multilayer media were obtained with the thicker underlayer. Furthermore, the distribution of [111] orientation of FCC-Pd became broader, and the grain size decreased with an increase in the carbon underlayer thickness. These effects caused the magnetic exchange decoupling of Co/Pd multilayer media. We suggested that the change of microstructure was directly related to the surface roughness of the amorphous carbon underlayer. (C) 2001 Elsevier Science B.V. All rights reserved.

Cinchona-alkaloid/Selectfluor combinations efficiently fluorinate a variety of carbonyl compounds in a highly enantioselective manner to furnish chiral alpha -fluorocarbonyl compounds. The DHQB/Selectfluor combination is effective for the enantioselective fluorination of indanones and tetralones 1 in up to 91% ee. The first enantioselective syntheses of chiral derivatizing reagents 3 was accomplished with high ee and in high chemical yields by the DHQDA/Selectfluor combination. 3-Fluorooxindoles 7 were prepared with ee up to 83% using the (DHQ)zAQN/Selectfluor or the (DHQD)(2)PYR/Selectftuor combination. Since the combinations are conveniently prepared in situ from readily available reagents, the present system represents a practical method for enantioselective fluorination. X-ray crystallography and H-1 NMR analyses of the cinchona alkaloids/Selectfluor combination have established that the species that mediate this novel reaction are N-fluoroammonium cinchona alkaloid tetrafluoroborates, which adopt open conformations.

The effect of amorphous carbon underlayers on magnetic properties and read-write characteristics of Co73Cr18Pt6Ta3 single layer and Co/Pd multilayer perpendicular magnetic recording media were investigated. The increase in H-c and decrease in alpha, defined as 4 pi (dM/dH)(H=Hc), were observed by increasing the underlayer thickness for both Co-73 Cr18Pt6Ta3 and Co/Pd media. The media with a low alpha value, suggesting a decrease in the exchange coupling, exhibited the higher coercivity and the improvement of S/N ratio. In read-write experiments, the improvement of S/N ratio for the Co/Pd media was achieved up to 400 kFRPI or even higher in the recording density by increasing carbon underlayer thickness, while that for the Co73Cr18Pt6Ta3 media was obtained up to ca. 250 kFRPI.

Sputter-deposited amorphous carbon was applied as an underlayer for a Co73Cr18Pt6Ta3 Single layer perpendicular magnetic recording medium. It is shown that the amorphous carbon underlayer can control the Co [001] preferred orientation of the Co73Cr18Pt6Ta3 magnetic recording layer and that the microcrystalline structure, magnetic properties, and read-write characteristics of Co73Cr18Pt6Ta3 media are greatly dependent on the carbon underlayer thickness. By x-ray diffraction experiments and transmission electron microscopy observations, it was confirmed that the distribution of the c-axis orientation of Co grains becomes broader in the direction perpendicular to the film surface with increasing carbon underlayer thickness. Furthermore, the Co73Cr18Pt6Ta3 medium with a thick carbon underlayer indicated a relatively high perpendicular coercivity of 2800 Oe and an excellent signal to noise ratio in read-write characteristics. (C) 2000 American Institute of Physics. [S0021-8979(00)03324-7].

The influence of substrates on magnetic property and crystalline orientation of CoCrTa/TiCr perpendicular magnetic recording medium was investigated using a glass plate and a Si(1 0 0) single crystal. Magnetic measurements revealed that the film sputtered on a Si(1 0 0) substrate possessed a higher perpendicular coercive force than that on glass, where the pretreatment of the Si(1 0 0) substrate by aqueous HF solution effectively improved the magnetic properties. X-ray diffraction analysis of the films indicated that the crystallinity of the TiCr layer formed on the Si(1 0 0) substrate with the HF pretreatment was higher than that on the glass substrate. It was also found that CoCrTa and TiCr layers on the Si(1 0 0) substrate with the KF pretreatment had a narrower distribution of their c-axis orientation than those on glass substrate. The results of X-ray diffraction analysis were consistent with those of the TEM observation for cross-section bright- and dark-field images and the corresponding THEED patterns. These results suggest that the crystalline surface of the Si(1 0 0) substrate with HF pretreatment has the effect of inducing preferred orientation in the TiCr underlayer, which leads to a decrease in distribution of the c-axis orientation of Co grains in the CoCrTa layer, resulting in an increase in the perpendicular coercive force. (C) 2000 Elsevier Science B.V. All rights reserved.

The effect of magnetic pole shape on the remanent magnetization state at the track edge was studied for a ring-type head and a single-layered perpendicular medium system. An MIG head and a merged MR head were used for recording. These heads have symmetric and asymmetric magnetic pole structures, respectively. It was found that the remanent magnetization state at the track edge of a single-layered perpendicular medium was greatly influenced by the shapes of the magnetic poles. Thus it is necessary to improve the shape of magnetic poles in order to realize the higher track density for a single-layered perpendicular medium.

Perpendicular/longitudinal composite media were fabricated by sputtering. It is hard to deposit a perpendicular upper layer on a longitudinal underlayer because of the epitaxy between the layers. Therefore, it is important to prevent the epitaxial growth between the perpendicular upper layer and the longitudinal underlayer. For this purpose, we attempted to apply an amorphous carbon interlayer. First, the magnetic properties of perpendicular single media with Ti-Cr and C underlayers were compared. As a result, it was found that a perpendicular single medium with a C underiayer had the same property as a medium with a Ti-Cr underlayer. In accordance with these results, a perpendicular layer was deposited onto a longitudinal layer with a C interlayer. Consequently, the thickness of the C interlayer was optimized. As a result, a perpendicular/longitudinal composite medium was successfully fabricated using 5-nm C interlayer.

The components of the gyration tensor of the enzyme lysozyme were measured by using the HAUP method: g(11) = - 0.90 x 10(-5) and g(33) = 1.05 x 10(-5) at 303.4 K and a wavelength of 4880 Angstrom. The optical rotatory powers along the a and c axes in the same conditions were calculated: rho(a) = -21.3 and rho(c) = -24.8 degrees cm(-1). The optically active property of lysozyme is strange in that, although it contains a considerable quantity of alpha-helices (about 30%), the rotatory powers are unexpectedly small in magnitude, one order of magnitude less than those of quartz and with very large anisotropy. A conceptual consideration of this phenomenon is given. In order to assess the difference between the structures in both crystalline and solution states, the chirality index r was calculated to be 0.16. This value indicates that the structural change of lysozyme from the solution into the crystalline state is expressed by an increase of 19% in optical activity. From the NMR results [Smith et al. (1993), J. Mol. Biol. 229, 930-944], it is anticipated that the r value reflects the increased constraint in atomic motion in the side chains of exposed amino acid residues in the crystalline state.

Optical gyration G, birefringence Delta n and their electric-field E dependences of transparent ceramics of Pb0.92La0.08(Zr-0.65 Ti-0.35)(0.98)O-3 were studied by using high accuracy universal polarimeter (HAUP) in a temperature range between 10 degrees C and 130 degrees C. The high-temperature phase manifested neither spontaneous nor induced G, while the low-temperature phase did characteristic hysteresis loops of G and Delta n with respect to E. Group-theoretical consideration of gyro-optical properties of both phases led us to the conclusion that the high-End low-temperature phases are cubic T-h and trigonal C-3, the same as found in Pb0.92La0.08(Zr0.70Ti0.30)(0.98)O-3 ceramics. The free energy function of both phases was determined by using these electro-optic effects. It is found that both ceramics undergo the same phase transition and manifest similar dielectric and optical properties.

In a project of revealing gyro-optical properties of amino acids that build up proteins, all the components of the gyration tensor and the birefringence of L-aspartic acid have been successfully measured as a function of temperature although the crystal belongs to the mono-clinic system. The temperature dependence of the rotation of the gyration surface around the crystal lographic b axis was also clarified. It is of interest that the chirality index of this crystal was found to be almost the same as that of glutamic acid, another amino acid.

Temperature dependences of thermal strains of superconducting Bi2Sr2CaCu2O8 were measured by using the two-dimensional reciprocal-lattice method of x-ray diffraction in the temperature range between 15 and 300 K. Accuracies of measuring the lattice strains attained 1.6 x 10(-6). Very small anomalies of the lattice constants and lattice volume took place at T-c of the transition point. They were caused by definite discontinuities of the thermal-expansion coefficients. Using previously reported values of specific heat and isotropic compressibility a nearly temperature-independent equivalent Gruneisen parameter gamma(T) was derived as 0.89 +/- 0.11. From the extrapolation of the lattice volume of the high-temperature phase into the superconducting temperature region, additive lattice strains were found to appear spontaneously in the superconducting phase. From this fact it was concluded that a structural phase transition of the second order took place with the onset of superconductivity.

It has been known that oxo amide crystals made up of achiral molecules can be photochemically converted into optically active beta-lactams by irradiation with a high pressure mercury lamp. Although the oxo amide crystal belongs to an enantiomorphic class D-2, its optical activity could not be detected so far. We successfully measured the components of the gyration tensor of the oxo amide crystal by using the HAUP (high accuracy universal polarimeter) method: g(11) = -3.5 x 10(-4) (-79 degrees/mm), g(22) = -1.4 x 10(-4) (-32 degrees/mm), g(33) = -3.0 x 10(-4) (-68 degrees/mm) at 305 K, where the optical rotatory powers are indicated in parentheses. It has been proved by direct experiments that the optical activity of the reactant and the product in this reaction system remains unchanged over the photocyclization process.

As the first study on gyro-optical properties of amino acids, temperature dependences of the gyration tensor components of L- and D-glutamic acids were measured by using the HAUP (high-accuracy universal polarimeter). It was confirmed that the corresponding tensor components of the two enantiomers are the same in magnitude but opposite in sign. It is proposed that r = (rho(C)(0) - rho(S)(0))/rho(C)(0) be defined as the 'chirality index', where rho(C)(0) and rho(S)(0) designate rotatory powers per molecule in a crystal and in a dissolved state in liquid, respectively. It represents a measure of structural contribution of optical activity (OA) in a crystal. This value is 0.992 in glutamic acids.

A fundamental optical study was performed on superconducting Bi2Sr2CaCU2O8 by Using a high-accuracy universal polarimeter (HAUP). As this crystal is strongly linearly dichroic, we developed the extended HAUP theory which includes the treatments of the optical dichroisms. After having determined the optical nature of the crystal, we applied the extended HAUP method to a thin (001) plate specimen with light traveling to the front and rear directions in the specimen. These two experiments permitted us to separate the reciprocal and nonreciprocal optical effects. No sign of the nonreciprocal effects was found in the HAUP transmission experiment. A gyration tensor component g(33) takes place suddenly at T-c (90 K), increases with decreasing temperature, and reaches 1.87X10(-4) (36 degrees/mm of rotatory power) at 15 K. A steep change of birefringence hn with temperature also occurs below T-c. From the behaviors of g(33) and Delta n with temperature, it can be concluded that the crystal undergoes a second-order phase transition at T-c into an optically active class. The crystal manifests large linear dichroism, i.e., Delta m=-2.2X10(-2).

Temperature and biasing electric field dependences of a gyration tensor component g(12) of ammoniumu sulfate were measured by using the high accuracy universal polarimeter, HAUP, together with birefringences. g(12) was found to appear abruptly at the Curie point and to keep the constant value irrespective of change of the temperature. The x-rays two-dimensional method was applied for measuring the lattice strains from 300K down to 6K.

The symmetry changes of the gyration tensor components of the solid polymers with a spiral orientation am clarified with respect to the changes of the density distribution function of the constituent crystallites. Any constituent crystals of optically active polymers should be regarded as uniaxial and enantiomorphic as far as the gyration is concerned. When the density distribution becomes perfectly homogeneous in the three-dimensional space, the gyration tensor components are reduced to a single component, (8)over bar&gt;. Two rotatory powers of poly-L-lactic acid are compared; one is calculated from measured values in the solid state, the other is a measured value in chloroform solution by Goodman and D'Alagni. It is striking that the former is 10(3) times larger than the latter. This means that the helical conformations of the residues which clearly exist in the solid state are destroyed in the liquid solution.

The methods of measuring optical activity of solid polymers are reviewed. The extreme difficulty of the methods is exhibited in serious drawbacks of the traditional statistical methods. The invention of HA UP (high accuracy universal polarimeter) method by Kobayashi et al has opened a way to perfect measurements of gyro-optical properties of any solids. As an example of application of the HAUP method to helical polymers, the process of analyzing the gyration tensor components of poly-L-lactic acid and poly-D-lactic acid is illustrated in details. © 1995, Taylor &amp
Francis Group, LLC. All rights reserved.

Electric field dependences of optical activity and birefringence of Pb0.92La0.08(Zr0.7Ti0.3)(0.98)O-3(PLZT(8/70/30)) were studied using the high-accuracy universal polarimeter (HAUP) method in a temperature region between 0 degrees C and 90 degrees C. PLZT(8/70/30) was optically active in the low-temperature and inactive in the high-temperature phases. Furthermore it was revealed that gyration and birefringence in the low-temperature phase manifested typical butterfly hysteresis loops with respect to electric fields. From analysis of Weissenberg photographs, the ceramics of both high- and low-temperature phases were found to consist of crystallites which were distributed in equal weight along the total solid angles. Using the combined evidence from HAUP and X-ray methods, it was clarified that the classes of the high- and low-temperature phases are T-h and C-3, respectively.

Optical properties of PLZT(8/70/30) in various phases were studied by using HAUP method. Ferroelectric phase was found to be optically, active. From this result, it was revealed that the point group of PLZT should be C3 in the rhombohedral system(ferroelectric phase). Peculiar electric field dependences of gyration and birefringence in the intermediate phase were found. © 1994, Taylor &amp
Francis Group, LLC. All rights reserved.

Temperature dependences of gyration tensor component g11 and birefringence An of Gd2(MoO4)3 were measured at various wavelength by using high accuracy universal Polarimeter (HAUP). Spontaneous values of gn and An in the ferroelectric phase increased with decreasing temperature, but quadratic relations with respect to spontaneous polarization did not hold. The spontaneous Ans showed an anomalous peak at a wavelength of 334.7nm. Such a phenomenon has not been reported to date in any ferroelectrics. © 1994, Taylor &amp
Francis Group, LLC. All rights reserved.

Optical activity of a helical polymer, poly-L-lactic acid, was studied by using x-rays and HAUP methods. Gyrations depend considerably on the drawing actions. From the relation between gyrations and drawing ratios, the gyration tensor components are determined as g(1)=(-2.7 +/- 0.5) x10(-4) and g(3)=(8.3 +/- 0.2) x 10(-2). It is striking that a helical polymer like this material produces huge gyration along the helical chain.

Optical properties of La-modified lead zirconate titanate (9/65/35) in the intermediate phase were studied by the HAUP (high accuracy universal polarimeter) method. It was found that this material is optically inactive under electric fields. On the other hand, temperature dependence of the quadratic electrooptic coefficient was measured after careful corrections using the HAUP method.

Optical properties of pyroelectric and antiferromagnetic BaMnF4 were studied by using a high-accuracy universal polarimeter in the temperature range including the incommensurate phase transition point T(i). Both phases above and below T(i) were found to be optically active. The active gyration tensor components g(ij) were consistent with the reported symmetry of the crystal, i.e., C2-upsilon and C2 above and below T(i). Temperature dependences of all the gyration components were measured. It is striking that g23, which exists commonly in both phases, manifested itself a sharp peak at T(i). This divergence of g23 makes the transition perfectly second order. g11 along the incommensurate a axis develops conspicuously. The present results of the birefringences did not perfectly agree with previous reports: Although the temperature dependence of DELTA-n(c) coincided with the result of Schafer et al., those of DELTA-n(a) and DELTA-n(b) were quite different in their report. Rotation of the indicatrix takes place only around the a axis of the low-temperature phase. This fact confirms the validity of the point group C2 of the low-temperature phase. The rotation angle of the indicatrix was found to be one order of magnitude larger than that of the crystallographic axes. The rotation angle of the gyration surface was also evaluated. It is approximately two orders of magnitude larger than the rotation angle of the indicatrix. This fact clearly indicates that gyrations are very sensitively affected by the change of the order parameter.

Simultaneous measurements of the gyration, birefringence, and rotation angle of the optical indicatrix of Rochelle salt were successfully performed by using high-accuracy universal polarimetry. The three phases of the crystal were found to be optically active. It was revealed that the origin of ferroelectricity of the crystal is directly responsible for the occurrence of the optical activity. Birefringence in the ferroelectric phase cannot be explained by the usual electro-optic effect. Two possibilities are considered for this discrepancy.